Hooked up to my dump trailer this morning and the bed won’t power down. I store it with the bed about halfway up to drain rainwater and it’s always worked fine. Powers up normally, when I hit the down button the pump makes a screeching noise and the bed creeps UP instead of down. I guess there’s a valve stuck but I have no idea where to even start. Any help is much appreciated. Trailer is a 2017 Forest River, not used much and battery is good.