Bike Motor Surging after fixing a rear flat.

I recently ran over a staple and punctured the rear tube on my Juiced Jet Current, I took it to my local bike shop that works on E Bikes and they replaced the tube but when I test drove it the motor would surge and the cut off, surge then cut off. Anybody have any ideas on what this could be caused by? We re-checked the motor connection and everything looked good. That’s just leaves the cadence sensor or torque sensor for the next options that I could think of. So it’s still at the shop. But since Juiced doesn’t exist anymore this group is the best option for answers :) 🤞