Hi i want to tell all of you concerned about how to bypass KG: Prenormal aka "only official binaries are allowed to be flashed"
Note Note Note: You have to keep Wifi Connected!!
1: Connect device to Wifi
2pen developer options( tap build number 7 times)
3:You will see there is no OEM button but do not worry
4:Go back to home screen and go again to developer options do this 3-4 times and you will be greeted with OEM button. Hurrah!
Important NOTE: If After trying the loop of going to developer options and homescreen several times does not show OEM button for you then Go to settings-Apps-Show system-Settings App-Clear Data.
Now open developer options and do the loop of going to developer options and homescreen you will see OEM Button and in Bootloader KGrenormal will be KG:checking and you could flash unofficial binaries
** I have tried this on dozens of Samsung phones including S9+ on Android 10
Yes it works all of you any problem comment below i will help.