According to the owner's manual for my '96, if the power is interrupted the seats (and other things) require synchronization. If they are not synchronized, the system may think the seat is all the way up when it is not, and stop actuating the motor.

Try moving the control to put the seat to the bottom on the front and back, each time holding the control for an additional five seconds after the motor stops turning. Then see if it raises further.

I say "according to the owner's manual" because disconnecting the battery in my car apparently does not cause this synchronization to be lost. Even the memory is retained. But it appears that my car is special. Or it is haunted. I don't know.