Identity Safe Vault closes repeatedly

I am running Norton 360  20.3.1.22.  I have Identity Safe set so that it should only ask for password at beginning of each log-in session.  However, it closes about 4 or 5 times for no apparent reason during a 1 - 2 hour internet session.   I have Windows 7 Home Premium with SP 1.

 

Anything I can do to stop from having to log-in continually?

 

Thanks.