The drivers side seat heater does not work?

The first thing I would do is check the fuses for the seat here is a guide to help and the seat wiring diagrams below so you can see how the system works and which fuses to check.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

If the fuses are okay it sounds like the seat positioning module has gone out. Check out the images (Below). Please let us know what happens.