Depth Hold Problems?

Hi guys!
I’m trying to use my BlueRov2, which was out of use for over two years. It’s still a great vehicle, but when I change to stabilization or auto depth modes, it seems like all the thrusters go into high RPM, and the ROV goes completely crazy. I have had this problem since I first used it (in 2018), but I haven’t fixed it before. I would be grateful if someone could help me fix this problem and tell me what updates I should make to have everything working the best way.
Thanks in advance.