Can't flash any code on STM32WB55 after AES Key provisioning for SBSFU

[MBuen.1]

Hello community, how are u?

Hope everyone is well and safe =)

I'm developing an application using SBSFU. While testing the examples (withoout provisioning a AESKEY, only flashing SBSFU engine) i could always return my microcontroller to factory, just changing the RDP option byte in STM32CubeProgrammer. After doing that, all code of my microcontroller was erased and i was able to use it normally again.

My problems began when i provisioned AES KEY to CM0 CPU.To return to factory, i tried to do the same procedure i described above, but when i try to flash a new firmware i keep receiving a message from IDE that "Flash erase was not possible in sector 1-79", even though i'm able to erase and read the flash using STM32CubeProgrammer. All my write protections, read protection and PCROP are disabled. I'm not able to flash a firmware using STM32CubeProgrammer aswell, i get a message of "Flash download error".

Previously the AESKey provisioning i was able to factory reset, now i'm not and to make matters worst i erased my SBSFU engine. Any hints?

Tried to flash using VSCode (MakeFile), MDK-ARM and STM32CubeProgrammer. All these 3 choices failed aswell.

[MBuen.1 · Accepted solution]

Manage to do it =))

For that i needed to check PCROP protection to erase flash if RDP were decreased. Then i increased and decreased RDP and everything became back to factory again.