After replacing the battery and back cover on my iPhone 4S, I replaced the pentalobe screws on the bottom of the phone with phillips screws from the iFixit liberation kit.
I'm having two problems:
1) The screws are not flush with the bottom edge of the phone and won't go in any farther. They are almost all the way in, but not quite.
2) The screws won't come out. I can turn them clockwise or counterclockwise, but they don't go in or out. They just spin in place.
Neither of these is a big problem right now, though I'd prefer that the screws go all the way in and sit flush. My concern is that I can't open up the phone if I need to make another repair in the future.
Any idea what is going on here? Is there anything I can do about it?