Mine also pushes up against the ceiling but I'm not sure if it moves that much.
The bunk uses a similar mechanism to the slide (Schwintek) which means:
Always raise it all the way up or all the way down (which means the seats have to be forward and reclined enough so the bunk clears the seatbacks)
When all the way up or down hold the switch for an additional 3-5 seconds to sync the motors
Try not to stop anywhere in the middle and don't "reverse course" 1/2 way through
Having said all that: I picked up a foam mattress for our bunk that is too thick to stay on the bunk when all the way up. So when we're camping we'll raise it up until the mattress touches the ceiling (which leaves it about 1" down) but then lower it all the way down when its used for the night (again holding the switch for the extra 3-5 seconds on the bottom). So far after 4 seasons our front bunk hasn't given us any issues.