Google Play Crashes after payment successful

I get the crash after Payment successful I attached the Log device, I suspected to issues"java.lang.NullPointerException".maybe this error comes from UE4.17 because we have no such issues in UE4.16.and using many alternatives way to fix this problem such as delete play store app and etc…
any help would be appreciated.


I have also this problem in UE4.18.

i checked my log and i find this Class not found when unmarshalling: