I've been getting back into the Gazelle for the first time in a while, and I'm struggling to get the helicopter to engage and stay in auto-hover mode. I can get the auto-pilot to turn on (amber light) and get it within the required parameters. Once this occurs, the light will turn green, as it is supposed to. However, when I release my stick, the helicopter just falls to the left and disengages the auto-hover. How can I get it to stay in the auto-hover mode, as opposed to it rotating to the left and disengaging?