Problem with unread messages that cannot be read after a call

When the call function is used, unread messages for the call will be generated.
However, after the user has read the message, if the settingsClearCache is executed,
the unread messages will pop up again and cannot be cleared normally
(generally transmitting messages does not have this problem).
If we want to correct this problem, where should we start?
1. Synchronize the unread count on the client side with the count of the database on the server?
2. Does the notification of the client call need to be corrected?