diff --git a/core/java/com/android/internal/widget/VerifyCredentialResponse.java b/core/java/com/android/internal/widget/VerifyCredentialResponse.java
index ad6020c..7d1c706 100644
--- a/core/java/com/android/internal/widget/VerifyCredentialResponse.java
+++ b/core/java/com/android/internal/widget/VerifyCredentialResponse.java
@@ -98,6 +98,8 @@
             if (mPayload != null) {
                 dest.writeInt(mPayload.length);
                 dest.writeByteArray(mPayload);
+            } else {
+                dest.writeInt(0);
             }
         }
     }