Offline and Archive message show as ????

I use Spark 2.7.1 and openfire  3.10.2 for chat application and have two problem:

1. Problem with offline message encoding :
   • user A send message to user B(is offline) , user B can received offline message but when user A use Persian character user B see message like '????'.
   • etc problem for Archive . if any user send Persian character in archive shown ??????

please help me !

bests