The drum will not spin anymore. The drum turns

the most common problem is a broken DOG ASSEMBLY.

Pull off the softener dispenser
pull off the cap
take out the bolt
pull off the top of the agitator
you should see a broken plastic piece laying there
real cheap to buy one

next thing to check is the top door safety switch, does it click when you lower the door? Is the switch actuator broken off of the door?

Anything else is EXPENSIVE to fix.