I installed this rom which is 8.1.0 then i was plan to move down to original stock rom because of some major issue is with this custom rom. Thing is when i rollback to android 7.0 official i got a software updating notification approx 40 mb update size. when the update has been completed it's required a restart till today my phone is not getting a start .after researching i found some tips - i flash blankflash and phone really start with a dummy bootloader. now when i am trying to install "fastboot flash partition gpt.bin" it's saying this is downgrade version. what is an alternative ?
Always flash the latest version of the stock rom! The latest version is the December patch version!
Use this! And flash gpt.bin and bootloader.img first... Then restart to bootloader.. And then flash the whole rom! As per instructions in the thread!
Just in case u need a visual presentation watch this!