Hi, I own a Gionee P2 and the phone is kinda awesome especially for it's price. I honestly can't say the exact thing that happened to it but I have successfully rooted the phone. I was using it as hotspot when the internet stopped going and the phone went off automatically after a while. On turning on the phone again, it showed me NO SIM CARD DETECTED in both SIM 1 and SIM 2.
I have been searching all over the internet for a solution to the point that I have even followed the instruction on flashing it using Walton Primo f2 firmware which was successful and changed the phone software to walton but the issue of NO SIM CARD persists.
Also i noticed even before the flashing that the USB debuggin is always on and refused to be turned off. even after flashing the phone, the same thing still happens whenever I connect it to my PC. Please, I need help from anyone that has very good understanding of android or how to make ROMs.

NB: I have used MTK-droid tool to make a backup from a friend who uses the exact same Gionee P2 but how to compile that into the installable ROM is what I don't know. Please help if you have any idea. Thanks in advance