You sure? Double tap the home button and swipe to the left. Make sure screen rotation lock is off. Make sure the side switch is in the off position. You may need to manually change the screen orientation. Go into settings>accessibility>assistive touch. Tap the switch to turn it on. A white dot should show up in the bottom corner of the screen. Tap the dot, tap device. Make sure the screen rotation is off here. If it is off and the screen is still stuck, tap device. Then, select the orientation you would like to rotate the screen to. Hopefully this will work. Also, make sure your version of iOS is up to date. Plug it in to iTunes and check for updates. If all this doesn't work, you may have to restore from a backup. If all else fails, take it to the genius bar.