I have had my galaxy s4 for almost a month and love it, but it recently had a software update and ever since the screen rotation is not working. The camera is always upside down. Occasionally if the screen rotates to landscape, it won't rotate back to portrait when I turn the phone back the other way. I have tried to restart the phone. I have unchecked and rechecked the auto screen rotate setting. Nothing fixes it. Any ideas as to what is causing this and how I can fix it?