Error when customer is trying to switch store commerce offline

The user logs into POS and changes the password, then log into another POS register (from a different device) and is trying to switch to offline. Customer wants to login into offline mode after successfully login to Online mode

 Basically customer want it to work like this. Any time I sign in to POS in online mode successfully, then set (reset) my credentials encrypted credentials in the offline database to the values I just used. By doing this I will always be able to log in in offline mode after I successfully login in online mode.