Login password removed and disabled after reboot

[mahesh]

Hello!

I am new to Linux and my system is a portable Ubuntu 20.4 on a USB stick. I have set a password for my account (it's my first account after installing Ubuntu, so it is a super-user I suppose?) and I have disabled Auto Login in Setting > User. But every time after a clean reboot, my password is gone and I could just login without a password. I would set it again and it will be gone after another reboot. Logging out and back in without a reboot is fine (i.e. requires password). I have created a second user account w/o admin rights and that account has no such problem. Since I have been using my first account for a while with many saved settings, I prefer not to migrate to a new user account. Is there a way to solve this problem? Many thanks for any advice