Hi,
I noticed the very same behavior with the AIQUM instance I have running in my lab after upgrading to 9.10. (I don't see that problem on my 9.11 instance though)
The good news - the password is not incorrect. For whatever reason the admin account got locked.
Quick-fix: log in to the web UI with a different admin user (I hope you have another one) and unlock the admin user account.
Unfortunately it will get locked at some point again.
From preliminary troubleshooting it looks as if some internal process is using the admin account with an incorrect or default password. After multiple unsuccessful logins the account gets locked.
I suggest to open a support case.
Kind regards, Niels