Driver's seats gone jabberwocky!

Prolly not the right choice of word but how I feel! Anyway, while trying to put new seatcover on, I moved seat around to easily access underneath to attach "tension cords" to keep seatcover in place.

Pushed green button to go back to memorized position and about halfway thru, side of seat closest to outside of car starts going down into the pillar. Stop and try to manually adjust to no avail...seat is now out of whack!

Cousin says "common thing, rails get dirty and bind up. take seat out, clean and you'll be fine!" Neighbor comes over laughing "why the hell do you have the seat out of this thing?" I say to clean rails but I can't find them. He says they're right there and look pretty clean to me. Put seat back into car and same situation.

Any takers with some help? I did a search a while back and found about running to the full extent of the motors and have tried that to no avail...help!

BTW, 1995 E320 FWIW!