Main gear door issue

[Skymaster337B]

The way I see the diagram is, the main gear door pressure is trapped between the two actuators. This effectively hydraulic-locks the doors in place. So, my guess is there's an internal leak in one of your gear door actuators. Very easy to overhaul...mostly new o-rings, and of course a proprietary Cessna teflon "back-up seal" that will cost almost as much as socialized health care. The other possibility is the door solenoid in the power pack.