I've been having an issue with SIM1 slot on a Gionee GN5005 ever since I took it apart while attempting a ROM backup - https://forum.hovatek.com/thread-36791-p...#pid202671.
Only SIM1 slot has the issue:
* SIM isn't detected most of the time.
* It gets detected sometimes - but not for long - during which time I can dial USSD codes, or even connect to the internet.
* When it's detected, I can't make calls with it; it goes off when I pick a call on the line, and sometimes this occurs when I pick/make calls with SIM on slot 2.
* It doesn't matter what SIM I insert -- not a specific SIM issue.
* Rebooting doesn't fix issue.