Post originale di: Minho ,
If the Portrait Orientation Lock is turned off and you have tried to hard reset (Home & Power Button for ~10 secs) your device already, then the issue may be on the logic board. Inside, there is a gyroscope IC that detects the orientation of the device. If it failed, then it won't detect the change in orientation. This IC can be replaced but it requires a micro-soldering repair and is not DIY.