Well, I don't know what is making him 'flip' and not being there is impossible for anybody to figure it out but I can tell you that touching his back and under his wings is a no-no as both are erogenous zones and no animal (or human for that matter) appreciates getting all hot and bothered and getting 'no satisfaction' as the song goes
. The only places you can touch in a bird's body are its head, neck and cheeks - that's it, nowhere else.
The other thing I would underline is that they need strict daily routines, meaning, no changes from day to day or from week day to weekend (and I have found that this is one of the hardest things for people to do - our lives being so very up and down all the time). They have to wake up with dawn, fed before or as soon as the sun is coming into the room, turn artificial lights on at that point, allow to eat for half an hour or so, rest/nap in the middle of the day, lights off when sun is halfway down to the horizon, dinner a bit later (there should be no seed AT ALL during the day, only for dinner), complete darkness and quiet for a restful sleep at night. This is the same never changing daily routine they follow in the wild (it's called the circadian cycle) and what their bodies need because it's what they evolved to follow. They also need hours of flight because it's the ONLY thing that dissipates bad (sexual, stress) hormones from their bloodstream...