Cannot login to WP – phpmyAdmin changes don't stick

All;
Huge dilemma. Set new site live last night and at some point this morning I was all the sudden not able to login to my wp dashboard anymore. Tried all 3 usernames and passowords and password reset – nothing. Then had Inmotion support on chat for 2hrs, they’re tried to manually change it mhpmyadmin but no luck. Still can;t log in. What to do? Unfortunately do not have a database backup.