You can check the output of below cli and then you can see what the active sessions are:
Fxos#scope security
Fxos/security# show user-sessions local
Fxos/security# show user-sessions local detail
After you take the outputs, you can clear the sessions displayed with the following commands:
fxos/security # delete user-sessions local admin [session ID]
fxos/security # commit-buffer
Please open case to Cisco TAC if issue is still existing and also you might need to provide the show-tech to TAC.