This is twice now my J2 has stopped working (No movement up or down)

That joint is the only one that gives me trouble. After it stopped working the first time, I took the J2 joint apart, put it back together and it started working again... for about 30 min.

The motor driver works and has full power/signal.

The J2 motor works (I can hear it whine like it’s trying to turn, but the arm doesnt move in either direction)

When I took it apart last time, I ran the J2 motor without the arm and it worked as intended.

Has anyone else had difficulty out of this joint as well? If so, how did you fix it?