Here is a video showing how to repair the Frozen mini-gears on each seat back lower corners.
These gears (2 in each seat) block the henge movements and therefore the corner (1or2) will not move up the rear seat back from unfolded position.

Fix by unzip the sides only & unbolt 4 bolts & 2 screws. Take away the henge-fixture, support the outer side center head nut on the concrete floor (or alike) with an nut wrench top - then

Hammer the 2 thin gear-henge-flanges together (hammer big hard in center only) until the henge work again.
​​​​​​Assample seat and put it back in car for mounting.

There is no need to buy new motors, if the seat moves 1 corner but not 2nd. Then The motor work !

Note if you have faults of functions DO NOT HELP THE SEAT MOVING but fix the problem. If you help the very powerfull motors they can flip the stearingbrods around and even twist the henges & fixtures until they looks like a spring g break the rods & guides.

Prevent failures - grease spray all links & bushings & springs &bcables & guide with a little wd40 every 2 years (same apply to the adjustable food-brakes rods and links & screw-shaft).

https://youtu.be/ilKFw-hBD0k