diff --git a/src/main/java/org/cellocad/MIT/dnacompiler/BuildCircuitsSimAnnealing.java b/src/main/java/org/cellocad/MIT/dnacompiler/BuildCircuitsSimAnnealing.java
index a0822491..7685ccb7 100644
--- a/src/main/java/org/cellocad/MIT/dnacompiler/BuildCircuitsSimAnnealing.java
+++ b/src/main/java/org/cellocad/MIT/dnacompiler/BuildCircuitsSimAnnealing.java
@@ -313,7 +313,7 @@ private Gate getNextGate(LogicCircuit lc, Gate A_gate) {
             }
 
             //allow non-duplicate groups
-            if (!currentlyAssignedGroup(lc, g.Group)) {
+            if (!currentlyAssignedGroup(lc, g.Group) || isNextGateCurrentlyUsed(lc, g)) {
                 allowed_B_gates.put(g.Name, g);
             }