Right brake light mot working

You need to check for power and ground at the bulb socket. Was the fuse blown? That could be a good hint that there's a power short to ground in the system. If either power or ground are lacking, get out your meter and trace the circuits back to the source of the failure. If you want to find a specialist, here's a directory link for you: https://repairpal.com/chevrolet-repair-in-saint-peters-missouri