diff --git a/node/src/main/kotlin/net/corda/node/services/statemachine/FlowStateMachineImpl.kt b/node/src/main/kotlin/net/corda/node/services/statemachine/FlowStateMachineImpl.kt
index 144ea62d26..b78d5da6a0 100644
--- a/node/src/main/kotlin/net/corda/node/services/statemachine/FlowStateMachineImpl.kt
+++ b/node/src/main/kotlin/net/corda/node/services/statemachine/FlowStateMachineImpl.kt
@@ -186,7 +186,7 @@ class FlowStateMachineImpl<R>(override val id: StateMachineRunId,
 
     private fun checkDbTransaction(isPresent: Boolean) {
         if (isPresent) {
-            requireNotNull(contextTransactionOrNull != null)
+            requireNotNull(contextTransactionOrNull)
         } else {
             require(contextTransactionOrNull == null)
         }