It’s actually a limitation right now. AxCrypt does not work conveniently with multiple accounts. You’re signed out when you sign out – but you’re still connected to the same acount, and there’s no simple way to switch accounts.
For now, the workaround is to use the “Clear All Settings and Exit”, and then enter the other account – OR create two different Windows accounts – one for your work and one for your private user. This actually has many other advantages and is the recommended way, and is one of the reasons we have not put a high priority on multi-account use of AxCrypt.