Could you try the old commands:Tested in Rome 7702 + ASRock EPYCD8-2T + SMU Debug Tool v1.1.1, unfortunately typing 0x5A resulted in "Error SMU Write"
Code:
EnableOverclocking = 0x24
DisableOverclocking = 0x25
The SMU version gets detected, so this means the addresses are working. It's just the new 0x5A command not working. There's also a newer version of the tool with integrated address scanner, but it might lead to BSOD or other random issues and would need system power off/power on cycle.