Lost Data After Nougat Update. T-Mobile on Sprint Device

[rzrplp]

Hi All,
I have recently updated my Sprint device, which had the mobile data working flawlessly before updating. Now I want to fix it and I want to flash my device to a T-Mobile firmware but I kinda lost between forums. Where should I start? Can someone outline the steps for me?

Thanks!

 

[goonygugle]

Hi All,
I have recently updated my Sprint device, which had the mobile data working flawlessly before updating. Now I want to fix it and I want to flash my device to a T-Mobile firmware but I kinda lost between forums. Where should I start? Can someone outline the steps for me?

Thanks!

Start by flashing the latest T firmware to it , if that doesn't correct your data and its showing invalid sim then your device may have been re-locked which I'm seeing a lot of lately