SBSFU - can not connect to STM32WB5M - Error: ST-LINK error (DEV_TARGET_CMD_ERR)

[CBuch.1]

I think i bricked my chip but dont know what happened and how i could revive the chip. The Error when i try to connect with STM32CubeProgrammer is: "Error: ST-LINK error (DEV_TARGET_CMD_ERR)"

What have i done to get to this state:

•  erase chip completly
• flash with sbsfu
• uart shows: "Applying RDP-1 Level. You might need to unplug/plug the USB cable!"
• restart device with unplug cable
• plug cable

After i can not connect again via STM32CubeProgrammer.

ST-Link Configurations are

• Port: SWD
• Frequency: 8000
• Mode: Under Reset
• Access Port: 0
• Reset mode: Hardware Reset

Output:

 

 14:33:37 : ST-LINK SN : 002C004A3331511534333834
 14:33:37 : ST-LINK FW : V3J10M3B5S1
 14:33:37 : Board : STLINK-V3MODS
 14:33:37 : Voltage : 3.30V
 14:33:37 : Error: ST-LINK error (DEV_TARGET_CMD_ERR)

 

I also tested all other modes.

 

With the st-util tool command "st-info --probe" i got the following output:

 

$ st-info --probe --connect-under-reset
Found 1 stlink programmers
 version: V3J10S1
 serial: 002C004A3331511534333834
 flash: 0 (pagesize: 0)
 sram: 0
 chipid: 0x0000
 descr: unknown device

 

so the st-link can not read the device information i think. What could be the Problem and what could i try?