Is my default password corrupted? Can it be reset?

I'm attempting to log into my second Atomic Pi for the first time. I was able to enter the first machine's password without issues. But the second machine rejects the password as invalid, although I've verified it & even tried alternates (1 for l, 0 for o). Is there any way to change or reset the default password for user atomicpi?

Thank to Justin Tamblyn's 2019 posting, I was able to use Ctrl + Alt + F2 to log in from the terminal instead of the login window. I then saw that the password which appeared to start with '1' actually started with 'i'. That solved my login problem. I then changed the atomicpi password to eliminate the problem.