diff --git a/android/olm-sdk/src/main/java/org/matrix/olm/OlmInboundGroupSession.java b/android/olm-sdk/src/main/java/org/matrix/olm/OlmInboundGroupSession.java
index f5173c3..8c2d7b0 100644
--- a/android/olm-sdk/src/main/java/org/matrix/olm/OlmInboundGroupSession.java
+++ b/android/olm-sdk/src/main/java/org/matrix/olm/OlmInboundGroupSession.java
@@ -302,7 +302,6 @@ public class OlmInboundGroupSession extends CommonSerializeUtils implements Seri
         // sanity check
         if(null == aErrorMsg) {
             Log.e(LOG_TAG,"## serialize(): invalid parameter - aErrorMsg=null");
-            aErrorMsg.append("aErrorMsg=null");
         } else if (null == aKey) {
             aErrorMsg.append("Invalid input parameters in serialize()");
         } else {