Flashing Disco-WB5MMG with pyOCD core #0 is not halted

I am trying to flash a Disco-ST32WB5MMG with MBEd Studio. Thereby PyOCD throws an error. Flashing the .elf and .bin file via ST-Link works.

Setup:

• Windows 11 PC
• Disco-ST32WB5MMG
• MBED Studio
• MBED OS 6.15.1

Debug Commands: --target STM32WB55VGYx --erase=chip --frequency 1800000 --pack 'c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\cmsis-packs\Keil.STM32WBxx_DFP.1.1.0-small.pack' -O connect_mode=under-reset

0001113:CRITICAL:__main__:cannot read register r0 because core #0 is not halted
Traceback (most recent call last):
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\__main__.py", line 402, in run
    self._COMMANDS[self._args.cmd](self)
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\__main__.py", line 579, in do_flash
    file_format=self._args.format)
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\flash\file_programmer.py", line 157, in program
    self._loader.commit()
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\flash\loader.py", line 168, in commit
    keep_unwritten=self._keep_unwritten)
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\flash\builder.py", line 464, in program
    flash_operation = self._chip_erase_program_double_buffer(progress_cb)
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\flash\builder.py", line 706, in _chip_erase_program_double_buffer
    self.flash.erase_all()
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\flash\flash.py", line 345, in erase_all
    result = self._call_function_and_wait(self.flash_algo['pc_eraseAll'])
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\flash\flash.py", line 604, in _call_function_and_wait
    return self.wait_for_completion()
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\flash\flash.py", line 600, in wait_for_completion
    return self.target.read_core_register('r0')
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\core\soc_target.py", line 173, in read_core_register
    return self.selected_core.read_core_register(id)
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\coresight\cortex_m.py", line 911, in read_core_register
    regValue = self.read_core_register_raw(reg_info.index)
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\coresight\cortex_m.py", line 928, in read_core_register_raw
    vals = self.read_core_registers_raw([reg])
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\coresight\cortex_m.py", line 949, in read_core_registers_raw
    return self._base_read_core_registers_raw(reg_list)
  File "c:\Users\JonasAlber\AppData\Local\Mbed Studio\mbed-studio-tools\python\lib\site-packages\pyocd\coresight\cortex_m.py", line 967, in _base_read_core_registers_raw
    self.core_number))
pyocd.core.exceptions.CoreRegisterAccessError: cannot read register r0 because core #0 is not halted

Start by reproducing the reported debug command with the Disco-ST32WB5MMG setup and trace the failure from pyocd/main.py through flash.py and coresight/cortex_m.py. The issue is resolved when chip erase and flashing complete without the core #0 not halted error.