Yeah, this one's common. The motor has thermal protection that kicks in if it gets too hot or is overloaded.
It usually means you're blending too much thick stuff for too long. Try smaller batches, especially with frozen items or nut butters. Also, use the pulsing function for thick mixtures instead of running it continuously.
Let it cool down for 15-20 minutes if it shuts off. It should reset and work again.