MAME 2003 squished :(

Hello, all! Noob here.

MAME 2003 suddenly squished the resolution on RetroArch on my PS Vita. All my portrait games now look square with blank borders at the top and bottom. MAME 2000 looks fine, but MAME 2000 doesn’t keep track of high scores automatically. Can anybody please tell me how to fix the resolution, or point me to the solution if this has been discussed?