I got a nice hard whack while racing the other day which put my steering out of whack veering the left of which the trim couldn't correct. I had to disconnect the servo, re-centre, adjust my trim and connect to servo to fix.

However since then it seems any small impact results in this happening again.
Very frustrating since i have to fix mid race meaning I come last.

I'm just a novice so not sure what to look at to fix.