diff --git a/fints4k/src/commonMain/kotlin/net/codinux/banking/fints/model/TanChallenge.kt b/fints4k/src/commonMain/kotlin/net/codinux/banking/fints/model/TanChallenge.kt
index 56425241..bda1b202 100644
--- a/fints4k/src/commonMain/kotlin/net/codinux/banking/fints/model/TanChallenge.kt
+++ b/fints4k/src/commonMain/kotlin/net/codinux/banking/fints/model/TanChallenge.kt
@@ -32,18 +32,24 @@ open class TanChallenge(
         this.enterTanResult = EnterTanResult(null, true, responseAfterApprovingDecoupledTan)
 
         userApprovedDecoupledTanCallbacks.forEach { it.invoke() }
-        userApprovedDecoupledTanCallbacks.clear()
+        clearUserApprovedDecoupledTanCallbacks()
     }
 
     fun userDidNotEnterTan() {
+        clearUserApprovedDecoupledTanCallbacks()
+
         this.enterTanResult = EnterTanResult(null)
     }
 
     fun userAsksToChangeTanMethod(changeTanMethodTo: TanMethod) {
+        clearUserApprovedDecoupledTanCallbacks()
+
         this.enterTanResult = EnterTanResult(null, changeTanMethodTo = changeTanMethodTo)
     }
 
     fun userAsksToChangeTanMedium(changeTanMediumTo: TanMedium, changeTanMediumResultCallback: ((FinTsClientResponse) -> Unit)?) {
+        clearUserApprovedDecoupledTanCallbacks()
+
         this.enterTanResult = EnterTanResult(null, changeTanMediumTo = changeTanMediumTo, changeTanMediumResultCallback = changeTanMediumResultCallback)
     }
 
@@ -56,6 +62,10 @@ open class TanChallenge(
         }
     }
 
+    protected open fun clearUserApprovedDecoupledTanCallbacks() {
+        userApprovedDecoupledTanCallbacks.clear()
+    }
+
 
     override fun toString(): String {
         return "$tanMethod (medium: $tanMediaIdentifier): $messageToShowToUser"