landscape to portrait freeze

[L_Boogie820]

Hey guys. I posted this in the Incredible section accidentally. It'll probably get moved or deleted. Anyway. I just got my incredible a couple days ago and now whenever I got from portrait to landscape then try going back to portrait, it just stays in landscape. It does it for everything. To test it out, I tried playing teeter and it doesn't work. Tilt nothing. It's not rooted, I have a tone of internal memory left. I don't know why its doing it. Pulled the battery, reset the phone as well. The option is checked off in settings for it to switch back and forth. What could it be?