Revert from 6.0 to previous?

[SakuraWulf]

I had whatever was before 6.0 and was able to play Pokemon Go. But, when I upgraded Go now won't work properly, telling me there is an issue with my gps location. It didn't have the problem before, I know the update caused it. How do I revert back to the one before 6? Hopefully without losing any info on the phone?

 

[efflandt]

Was that a normal update from your cellular provider? If you changed your system with firmware from elsewhere beyond what was normally provided for that phone, it might not have proper drivers for your hardware. So you would need to find previous firmware for your phone and provider.

I found out that once you even begin to try to root your phone, it can no longer get Android updates from your cellular provider, even if you do not complete the process because it detects that something changed in the boot sequence. I was just trying to root my phone to be able to edit the hosts file when connected to a VPN, but never got past the 1st stage of installing Odin(?). That was one factor that prompted me to buy a new phone (J7) in place of my 4 year old S3 that could do 4G, but not 4G LTE at a Black Friday sale last year.