I had a recent crash, and everything seemed okay, except for one thing. One arm won't lock. It will move up and I hear a click, but light finger pressure on pre-flight check pushes it down. I feel some pressure like it is almost there, but it won't fully lock. The arm hook and receiver for it appear to be in reasonable shape, so I don't know what else to check. Obviously I don't want to fly in that condition. Any suggestions on what to look for?