Quad flips on landing in Loiter - uneven ground?

I have had a few flips after/while landing that I would like a little help understanding.

I believe this normally occurs when I am landing in Loiter mode, which maybe I should just stop doing. I like flying in loiter mode.

The copter lands, (perhaps landing on sloped ground has something to do with this) the props do not go into armed idle mode, and part of the quad start to life back off. I then panic and try to disarm with the Tx, which doesnt disarm and possible just makes the flip worse since I am putting in full yaw at that point.

I believe that my simplest solution is to to just put it into stabilize with 0 throttle, (thats where the panic becomes a problem) So this question is more to develop understanding and know if the behavior I am seeing is strange or typical.

thanks!

Alex