Problems with JP Sterling bridge

My brother wanted me to take a look at his JP Sterling because after he restrung it, the action went way too high. (it was his first time restringing it and cut all the strings at once). at first I noticed the bass side was higher than the treble side so I tried adjusting it and it had a lot of resistance and made this “kachunk” sound. Now the bass side is WAY high. Is there a way I can bring it back to how it was before restringing or is it time to go to a guitar tech?