If its a new issue, you seemed to have lost your accelerometer. I had the same issue with my 920 and contacted Nokia and had it replaced under warranty.
try to switch off wifi, then soft reset the phone. I found this solution on youtube, but is too late for my phone :-(. it's already sent to repair. is this helped to you?
try to switch off wifi, then soft reset the phone. I found this solution on youtube, but is too late for my phone :-(. it's already sent to repair. is this helped to you?