My Lumia 1520 currently in wp8.1 dp, I am trying to downgrade it to the official wp8.1 because I have encounter many problem on dp such as every morning irresponsive screen, the phone heat up easily and always resuming. Both Lumia recovery tool and Lumia updater failed to downgrade the dp. First, when I connect my phone to PC, I cannot found my phone, then after that it want me to press hard reset then press ok, then it found my phone and it ask me to install. After download the update which is 1.67Gb, it either fail to go to next steps or it say my phone is not supported. Please help me, I really want to get rid of dp.