On the very bottom of the garbage disposal, you can insert a 1/4" allen wrench or a 6mm one, and then rotate it to free the jam. Then flush with water and try to run it again.

Technical notes, and other ideas.
On the very bottom of the garbage disposal, you can insert a 1/4" allen wrench or a 6mm one, and then rotate it to free the jam. Then flush with water and try to run it again.