A worn, slipped, or broken drive belt creates a distinctive problem: the dryer motor will be humming as usual, but the drum won't turn. Drive belt problems are also the most common reason a dryer won't spin.
Try to turn the drum with your hand. If your belt is intact, the drum won't move easily. If it has slipped or snapped, the drum will move fairly freely. Changing the belt takes a little DIY expertise because you'll have to remove panels to access it, and work around other components that may be in the way.
*GE Appliances technicians carry an extensive parts inventory on their service trucks. In the event a part is not available on the service truck, a follow-up service call may be required.