Error uploading new Firmware: board erase failed 0x11 Proto Failed

After uploading a custom firmware, now I can’t upload a new firmware on my Pixhawk board, I always get this error:

Error: Board erase failed: Send Command: Command failed: 0x11 (PROTO_FAILED)

Upgrade cancelled

Does anyone have a solution / suggestion?

I tried uploading a new firmware with Mission Planner, also failed, tried uploading a new bootloader with mission planner also without success.