As mentioned above, the most common answer to your problem is the
coils. Take the two screws at the lower front of the dryer out, rotate
the front away from the dryer, lean away from the dryer. You will have
access to the two coils on the valve assembly. Remove the bracket that
holds the coils in place by removing 2 Phillips head screws. Pull off
wire connector and replace each coil. They are very standard between
different brands, so you can actually install, for example, a Whirlpool
pair if they are cheaper.