G975F failed to remove demo mode

1) fully converted from g975x to g975f
2) rooted
but when try to remove demo chimera say FAILED

any suggestion? thanks

Gathering phone info…
Collecting information. Be patient! Do NOT disconnect the phone!
Model: SM-G975F
Carrier ID: MDL
Sales Code: XEF
Country Code: France
Timezone: Europe/Amsterdam
Android Version: 10 [QP1A.190711.020] [SDK 29] Build Date: Fri Sep 18 16:39:22 KST 2020
PDA Version: G975FXXS9DTI8 [september 2020, rev8] Phone Version: G975FXXS9DTI8 [september 2020, rev8] CSC Version: G975FOXM9DTI8 [september 2020, rev8] Board Platform: UNIVERSAL9820
Modem Platform: SHANNON5000
Serial Number: R58KC3C8G9T
Imei: 000000000000000
Network Type: GSM
SIM Status: ABSENT,ABSENT
Multisim Config: DSDS
Knox Version: v30
Warranty Bit: 1
Security Patch: 2020-10-01
Remove demo flag…
The operation is in progress. Be patient! Do NOT disconnect the phone!
Failed to remove demo flag.
Finished at local time: [02.22.21 19:33:47] WorkID: 125814374