Help with Resolution in RetroArch

I was playing around with the Video settings in RetroArch as all my games were loading half screen or 3/4 screen. I changed the magnification by selecting left on the Dpad, and now my resolution is significant modified. Every time i restart, i just see the green line and black pixels. I don’t know how to reset this. Can you please help. Also how do i get my snes games to play full screen?

so you want restore the default retroarch’s config in GameShell?

just ssh into gs

wget -O ~/.config/retroarch/retroarch.cfg