Do you have an input override for this game ? If you open the RetroArch menu and go to Controls/Port 1, what kind of device type does it say it is ?

Please add some more info about your setup, as detailed in https://retropie.org.uk/forum/topic/3/read-this-first.

@CubeBox391 there's a snes version of ms. pacman, which will work. there's a few other pacman games (although apart from ms. pacman they don't really play like the original):

basically anything that is actually a SNES game will work on the SNES emulators :)