1. When I get my S9 G960F, it's system is Android 8, so I flash latest android pie firmware ‘PDA: G960FXXU6CSG8, CSC: G960FOXM6CSG5’ which was released on 17th July 2019.
After flashed Android pie, I open 'OEM unlocking' by change the date method.
Then I found that I can’t flash TWRP into it by Odin with information ‘Only official released binaries are allowed to be flashed(RECOVERY)’.
2. I try to flash more older android pie firmware like ‘PDA: G960FXXU5CSF2, CSC: G960FOXM5CSF2’ which was released on 11th June 2019 by Odin,
show ‘KERNEL REV. CHECK FAIL DEVICES:6, BINARY:5 (BOOT)’.
I couldn't root it since TWRP couldn't flash into it.