diff --git a/miniapps/biobridge/src/App.test.tsx b/miniapps/biobridge/src/App.test.tsx
index a14e2a891..df106b90f 100644
--- a/miniapps/biobridge/src/App.test.tsx
+++ b/miniapps/biobridge/src/App.test.tsx
@@ -215,4 +215,44 @@ describe('Forge App', () => {
       expect.objectContaining({ method: 'eth_requestAccounts' })
     )
   })
+
+  it('should allow reconnecting wallets from confirm step', async () => {
+    mockBio.request.mockImplementation(({ method, params }: { method: string; params?: Array<{ chain?: string }> }) => {
+      if (method === 'bio_closeSplashScreen') return Promise.resolve(null)
+      if (method === 'bio_selectAccount') {
+        const chain = params?.[0]?.chain
+        if (chain === 'ethereum') {
+          return Promise.resolve({ address: '0xexternal-bio', chain: 'ethereum' })
+        }
+        return Promise.resolve({ address: 'bfmeta123', chain: 'bfmeta' })
+      }
+      return Promise.resolve(null)
+    })
+
+    render(<App />)
+
+    await waitFor(() => {
+      expect(screen.getByTestId('connect-button')).toBeInTheDocument()
+    })
+
+    fireEvent.click(screen.getByTestId('connect-button'))
+
+    await waitFor(() => {
+      expect(screen.getByTestId('amount-input')).toBeInTheDocument()
+    })
+
+    fireEvent.change(screen.getByTestId('amount-input'), { target: { value: '1' } })
+    fireEvent.click(screen.getByTestId('preview-button'))
+
+    await waitFor(() => {
+      expect(screen.getByText('0xexternal-bio')).toBeInTheDocument()
+      expect(screen.getByText('bfmeta123')).toBeInTheDocument()
+    })
+
+    fireEvent.click(screen.getByTestId('reconnect-button'))
+
+    await waitFor(() => {
+      expect(screen.getByTestId('connect-button')).toBeInTheDocument()
+    })
+  })
 })
diff --git a/miniapps/biobridge/src/App.tsx b/miniapps/biobridge/src/App.tsx
index 9854fa771..0304d71f0 100644
--- a/miniapps/biobridge/src/App.tsx
+++ b/miniapps/biobridge/src/App.tsx
@@ -39,6 +39,10 @@ import type { BridgeMode } from '@/api/types';
 
 type RechargeStep = 'connect' | 'swap' | 'confirm' | 'processing' | 'success';
 
+function normalizeIdForCompare(value: string | undefined): string {
+  return value?.trim().toLowerCase() ?? '';
+}
+
 const TOKEN_COLORS: Record<string, string> = {
   ETH: 'bg-indigo-600',
   BSC: 'bg-yellow-600',
@@ -229,6 +233,17 @@ export default function App() {
 
   const handleConfirm = useCallback(async () => {
     if (!externalAccount || !internalAccount || !selectedOption) return;
+    const expectedExternalChain = normalizeChainId(selectedOption.externalChain);
+    if (normalizeIdForCompare(externalAccount.chain) !== normalizeIdForCompare(expectedExternalChain)) {
+      setError(t('error.accountChainMismatch'));
+      setRechargeStep('connect');
+      return;
+    }
+    if (normalizeIdForCompare(internalAccount.chain) !== normalizeIdForCompare(selectedOption.internalChain)) {
+      setError(t('error.accountChainMismatch'));
+      setRechargeStep('connect');
+      return;
+    }
     const tokenAddress = selectedOption.externalInfo.contract?.trim();
     let effectiveExternalDecimals = resolvedExternalDecimals;
     if (tokenAddress && effectiveExternalDecimals === undefined) {
@@ -283,6 +298,15 @@ export default function App() {
     forgeHook.reset();
   }, [forgeHook]);
 
+  const handleReconnectAccounts = useCallback(() => {
+    setExternalAccount(null);
+    setInternalAccount(null);
+    setAmount('');
+    setError(null);
+    forgeHook.reset();
+    setRechargeStep('connect');
+  }, [forgeHook]);
+
   // Group options by external chain for picker
   const groupedOptions = useMemo(() => {
     const groups: Record<string, ForgeOption[]> = {};
@@ -577,14 +601,24 @@ export default function App() {
                   )}
 
                   <div className="mt-auto pt-4">
-                    <Button
-                      data-testid="preview-button"
-                      className="h-12 w-full"
-                      onClick={handlePreview}
-                      disabled={!amount || parseFloat(amount) <= 0}
-                    >
-                      {t('forge.preview')}
-                    </Button>
+                    <div className="space-y-2">
+                      <Button
+                        data-testid="preview-button"
+                        className="h-12 w-full"
+                        onClick={handlePreview}
+                        disabled={!amount || parseFloat(amount) <= 0}
+                      >
+                        {t('forge.preview')}
+                      </Button>
+                      <Button
+                        variant="ghost"
+                        className="h-10 w-full"
+                        data-testid="reconnect-button"
+                        onClick={handleReconnectAccounts}
+                      >
+                        {t('forge.changeWallets')}
+                      </Button>
+                    </div>
                   </div>
                 </motion.div>
               )}
@@ -636,6 +670,20 @@ export default function App() {
 
                   <Card>
                     <CardContent className="space-y-3 py-4 text-sm">
+                      <div className="flex justify-between">
+                        <span className="text-muted-foreground">{t('forge.sender')}</span>
+                        <span className="max-w-36 truncate font-mono text-xs">
+                          {externalAccount?.address}
+                        </span>
+                      </div>
+                      <Separator />
+                      <div className="flex justify-between">
+                        <span className="text-muted-foreground">{t('forge.receiver')}</span>
+                        <span className="max-w-36 truncate font-mono text-xs">
+                          {internalAccount?.address}
+                        </span>
+                      </div>
+                      <Separator />
                       <div className="flex justify-between">
                         <span className="text-muted-foreground">{t('forge.ratio')}</span>
                         <span>{t('forge.ratioValue')}</span>
@@ -677,14 +725,24 @@ export default function App() {
                   </Card>
 
                   <div className="mt-auto pt-4">
-                    <Button
-                      data-testid="confirm-button"
-                      className="h-12 w-full"
-                      onClick={handleConfirm}
-                      disabled={loading}
-                    >
-                      {t('forge.confirm')}
-                    </Button>
+                    <div className="space-y-2">
+                      <Button
+                        data-testid="confirm-button"
+                        className="h-12 w-full"
+                        onClick={handleConfirm}
+                        disabled={loading}
+                      >
+                        {t('forge.confirm')}
+                      </Button>
+                      <Button
+                        variant="ghost"
+                        className="h-10 w-full"
+                        data-testid="reconnect-button"
+                        onClick={handleReconnectAccounts}
+                      >
+                        {t('forge.changeWallets')}
+                      </Button>
+                    </div>
                   </div>
                 </motion.div>
               )}
diff --git a/miniapps/biobridge/src/i18n/locales/en.json b/miniapps/biobridge/src/i18n/locales/en.json
index 8083cd93b..c79d29304 100644
--- a/miniapps/biobridge/src/i18n/locales/en.json
+++ b/miniapps/biobridge/src/i18n/locales/en.json
@@ -28,7 +28,10 @@
     "decimalsLoading": "Loading decimals...",
     "decimalsFromTokenInfo": "token info",
     "decimalsFallback": "default",
-    "contractHint": "Contract: {{address}}"
+    "contractHint": "Contract: {{address}}",
+    "changeWallets": "Change wallets",
+    "sender": "Sender",
+    "receiver": "Receiver"
   },
   "redemption": {
     "title": "Redemption",
@@ -80,6 +83,7 @@
     "invalidAmount": "Please enter a valid amount",
     "decimalsLoading": "Token decimals are loading",
     "missingDecimals": "Missing token decimals configuration",
+    "accountChainMismatch": "Wallet account does not match selected chain, reconnect wallets",
     "forgeFailed": "Operation failed"
   },
   "picker": {
diff --git a/miniapps/biobridge/src/i18n/locales/zh-CN.json b/miniapps/biobridge/src/i18n/locales/zh-CN.json
index 19a3553d5..f92a1a0c5 100644
--- a/miniapps/biobridge/src/i18n/locales/zh-CN.json
+++ b/miniapps/biobridge/src/i18n/locales/zh-CN.json
@@ -28,7 +28,10 @@
     "decimalsLoading": "精度读取中...",
     "decimalsFromTokenInfo": "TokenInfo",
     "decimalsFallback": "默认",
-    "contractHint": "合约：{{address}}"
+    "contractHint": "合约：{{address}}",
+    "changeWallets": "重新连接账户",
+    "sender": "发送地址",
+    "receiver": "接收地址"
   },
   "redemption": {
     "title": "赎回",
@@ -80,6 +83,7 @@
     "invalidAmount": "请输入有效金额",
     "decimalsLoading": "精度信息加载中，请稍候",
     "missingDecimals": "缺少资产精度配置",
+    "accountChainMismatch": "账户与当前链不匹配，请重新连接账户",
     "forgeFailed": "操作失败"
   },
   "picker": {
diff --git a/miniapps/biobridge/src/i18n/locales/zh-TW.json b/miniapps/biobridge/src/i18n/locales/zh-TW.json
index faf8d70ce..8374d6afc 100644
--- a/miniapps/biobridge/src/i18n/locales/zh-TW.json
+++ b/miniapps/biobridge/src/i18n/locales/zh-TW.json
@@ -28,7 +28,10 @@
     "decimalsLoading": "精度讀取中...",
     "decimalsFromTokenInfo": "TokenInfo",
     "decimalsFallback": "預設",
-    "contractHint": "合約：{{address}}"
+    "contractHint": "合約：{{address}}",
+    "changeWallets": "重新連接帳戶",
+    "sender": "發送地址",
+    "receiver": "接收地址"
   },
   "redemption": {
     "title": "贖回",
@@ -80,6 +83,7 @@
     "invalidAmount": "請輸入有效金額",
     "decimalsLoading": "精度資訊載入中，請稍候",
     "missingDecimals": "缺少資產精度配置",
+    "accountChainMismatch": "帳戶與當前鏈不匹配，請重新連接帳戶",
     "forgeFailed": "操作失敗"
   },
   "picker": {
diff --git a/miniapps/biobridge/src/i18n/locales/zh.json b/miniapps/biobridge/src/i18n/locales/zh.json
index 19a3553d5..f92a1a0c5 100644
--- a/miniapps/biobridge/src/i18n/locales/zh.json
+++ b/miniapps/biobridge/src/i18n/locales/zh.json
@@ -28,7 +28,10 @@
     "decimalsLoading": "精度读取中...",
     "decimalsFromTokenInfo": "TokenInfo",
     "decimalsFallback": "默认",
-    "contractHint": "合约：{{address}}"
+    "contractHint": "合约：{{address}}",
+    "changeWallets": "重新连接账户",
+    "sender": "发送地址",
+    "receiver": "接收地址"
   },
   "redemption": {
     "title": "赎回",
@@ -80,6 +83,7 @@
     "invalidAmount": "请输入有效金额",
     "decimalsLoading": "精度信息加载中，请稍候",
     "missingDecimals": "缺少资产精度配置",
+    "accountChainMismatch": "账户与当前链不匹配，请重新连接账户",
     "forgeFailed": "操作失败"
   },
   "picker": {
diff --git a/src/services/chain-adapter/evm/transaction-mixin.test.ts b/src/services/chain-adapter/evm/transaction-mixin.test.ts
new file mode 100644
index 000000000..2a95f462b
--- /dev/null
+++ b/src/services/chain-adapter/evm/transaction-mixin.test.ts
@@ -0,0 +1,43 @@
+import { describe, expect, it } from 'vitest'
+import { hexToBytes } from '@noble/hashes/utils.js'
+import { privateKeyToAccount } from 'viem/accounts'
+import { recoverTransactionAddress } from 'viem'
+
+import { EvmTransactionMixin } from './transaction-mixin'
+import type { UnsignedTransaction } from '../types'
+
+class EvmSignTestBase {
+  constructor(public readonly chainId: string) {}
+}
+
+class EvmSignTestService extends EvmTransactionMixin(EvmSignTestBase) {}
+
+describe('EvmTransactionMixin.signTransaction', () => {
+  it('signs token tx with value=0x0 and keeps sender address consistent', async () => {
+    const service = new EvmSignTestService('binance')
+    const privateKeyHex = '0x59c6995e998f97a5a0044976f5d8f17f4b10df9589ef5f8a7f6f3f6db74ad5a4'
+    const expectedAddress = privateKeyToAccount(privateKeyHex).address.toLowerCase()
+
+    const unsignedTx: UnsignedTransaction = {
+      chainId: 'binance',
+      intentType: 'transfer',
+      data: {
+        nonce: 137,
+        gasPrice: '0x2faf080',
+        gasLimit: '0x249f0',
+        to: '0x55d398326f99059ff775485246999027b3197955',
+        value: '0x0',
+        data: '0xa9059cbb000000000000000000000000063096cbc147d5170e1b10fa4895bfa882c1d45e0000000000000000000000000000000000000000000000008ac7230489e80000',
+        chainId: 56,
+      },
+    }
+
+    const signed = await service.signTransaction(unsignedTx, {
+      privateKey: hexToBytes(privateKeyHex.slice(2)),
+    })
+
+    const serialized = signed.data as `0x${string}`
+    const recoveredAddress = (await recoverTransactionAddress({ serializedTransaction: serialized })).toLowerCase()
+    expect(recoveredAddress).toBe(expectedAddress)
+  })
+})
diff --git a/src/services/chain-adapter/evm/transaction-mixin.ts b/src/services/chain-adapter/evm/transaction-mixin.ts
index f860fcc01..fa23afb79 100644
--- a/src/services/chain-adapter/evm/transaction-mixin.ts
+++ b/src/services/chain-adapter/evm/transaction-mixin.ts
@@ -202,13 +202,16 @@ export function EvmTransactionMixin<TBase extends Constructor<{ chainId: string
                 chainId: number | string
             }
             const chainId = await this.#resolveChainId(txData.chainId)
+            const gasPrice = this.#normalizeQuantityHex(txData.gasPrice)
+            const gasLimit = this.#normalizeQuantityHex(txData.gasLimit)
+            const value = this.#normalizeQuantityHex(txData.value)
 
             const rawTx = this.#rlpEncode([
                 this.#toRlpHex(txData.nonce),
-                txData.gasPrice,
-                txData.gasLimit,
+                gasPrice,
+                gasLimit,
                 txData.to.toLowerCase(),
-                txData.value,
+                value,
                 txData.data,
                 this.#toRlpHex(chainId),
                 '0x',
@@ -228,10 +231,10 @@ export function EvmTransactionMixin<TBase extends Constructor<{ chainId: string
 
             const signedRaw = this.#rlpEncode([
                 this.#toRlpHex(txData.nonce),
-                txData.gasPrice,
-                txData.gasLimit,
+                gasPrice,
+                gasLimit,
                 txData.to.toLowerCase(),
-                txData.value,
+                value,
                 txData.data,
                 this.#toRlpHex(v),
                 '0x' + rHex,
@@ -259,6 +262,18 @@ export function EvmTransactionMixin<TBase extends Constructor<{ chainId: string
             return '0x' + n.toString(16)
         }
 
+        #normalizeQuantityHex(value: string): string {
+            const trimmed = value.trim()
+            if (!trimmed.startsWith('0x') && !trimmed.startsWith('0X')) {
+                return trimmed
+            }
+            const hex = trimmed.slice(2).replace(/^0+/, '')
+            if (hex.length === 0) {
+                return '0x'
+            }
+            return `0x${hex}`
+        }
+
         #rlpEncode(items: string[]): string {
             const encoded = items.map((item) => {
                 if (item === '0x' || item === '') {