My iPad Air cover was messed up on hover for about a week. Prior to that, when using the iPad Air, I often folded the cover around the back of the iPad when using it.
The "fix" happend overnight. I believe I had something small on top of the cover, not sufficient to press it all the way down, but it may have not been repelled as far off the surface.
I suggest closing the cover, with maybe a book or something non-magnetic like that on top of it, and leave it overnight. Repeat this on several nights. You may get lucky, like I did. You could also try leaving it closed overnight, upside down. If there is something in the iPad that moves, having gravity help might be worthwhile.
You should also lodge iPad Air feedback with Apple, so they have more complaints about this.
You probably should also lodge a support request with Apple, and retain the support number (you should still be under warrantee).
I have not (as yet) had a repeat of the problem.
Good luck.