VM8090 Set commands (21h, 42h) do not work!

i need a little help for VM8090 Relay-Boards.
Everything is working fine, except two commands:

  • Set button mode (21h)
  • Set relay timer delay (42h)
    This are commands to write in the EEPROM. When i try to give a command like this:
    04 21 FF 00 00 DC 0F (Set button mode (21h) enable momentary mode FF) or like this
    04 42 01 00 01 B8 0F (Set relay timer delay (42h) Relay1 HByte 00 LByte 01)
    there is no response and the sttings in EEPROM are the same as before…?!?
    That ist the only issue
    Can anyone help??
    Best regards

it was a usb connection problem