Dolphins tarts but gets stuck in one place

by Steve
(Winchester, VA)

My Dolphin advantage starts OK and moves along for a few minutes but it eventually gets to a sidewall and tries to climb it. The top propeller stops so it goes back and forth, in the same spot, until I shut it off. I have let it sit for up to an hour, but no change. I have turned it on and off and on again but always the same. It is 3 years old and worked fine until this season. It has not been left out during off season, it is stored in a shed next to the house.

Is there a reset switch or procedure?

What could be wrong?

I have tried to find a troubleshooting guide and this is the first site to have one.