Try change csc in XXV, note work.
Model : SM-G975F
Hardware : exynos9820
Modem : G975FXXUCFUH3,G975FXXUCFUH3
CSC Version : G975FOXMCFUH3
Android version : 11
Sales code : SER
Phone Carrier : CAU
Serial Number : RF8MB0S5HMK
Debug Level : 0x4f4c
Permissive : Enforcing
Warranty VOID : 0
SIM operator : ,
Sim State : ABSENT,ABSENT
initializing SIM: Success!
Getting Receiving data from server!
Reading data from Modem: Ok!
Reading CPID: Ok!
Reading MSL ID: Ok!
Reading IMEI Security: 356171103590351
Getting AUTH data from server!
Checking Support Models: Ok
Checking RIL: Ok!
Change CSC Processing!
Never disconnect the cable from the device Please Wait!
Rebooting: [CP level...OK]
Wait For Device...Ok
Rebooting: [DEBUG Mode...OK]
Installzing Applet Tool...Ok
Change CSC CODE...Ok
Operation Finished!
Model : SM-G975F
Hardware : exynos9820
Modem : G975FXXUCFUH3,G975FXXUCFUH3
CSC Version : G975FOXMCFUH3
Android version : 11
Sales code : SER
Phone Carrier : CAU
Serial Number : RF8MB0S5HMK
Debug Level : 0x4f4c
Permissive : Enforcing
Warranty VOID : 0
SIM operator : ,
Sim State : ABSENT,ABSENT
initializing SIM: Success!
Getting Receiving data from server!
Reading data from Modem: Ok!
Reading CPID: Ok!
Reading MSL ID: Ok!
Reading IMEI Security: 356171103590351
Getting AUTH data from server!
Checking Support Models: Ok
Checking RIL: Ok!
Change CSC Processing!
Never disconnect the cable from the device Please Wait!
Rebooting: [CP level...OK]
Wait For Device...Ok
Rebooting: [DEBUG Mode...OK]
Installzing Applet Tool...Ok
Change CSC CODE...Ok
Operation Finished!