That happened to me one time. My wife asked if the battery needed charging. I charged the battery and it worked again, both ways.
Try it, it might be an easy fix. My wife is always right when she puts her 2 cents in when there is a problem... John
I'm not sure if you're on hydraulic trim or a jackscrew. If it's the screw rig, and you're working one way and not the other I think I would have the motor looked at to see if it's running properly (spinnin' both ways). If that's not it, I'd swap out solenoids (just to check) and then it's probably on to the screw itself.
If it's the hydraulic set - I have no idea Never run one of those.