nRF52840 MDK USB Dongle; unable to get into bootloader mode

Whatever I try, the RGB-Led is only showing red color two times and then everything is green again.
What do you think: Broken board?
Is there another way to get into bootloader mode other then pressing and holding RESET and connecting the dongle to a computer.

The only thing I am getting when I insert the dongle into my computer is a com-port.

Thomas

Hi,
If you have flashed your own firmware to the dongle, the button may be changed to RESET pin. You may reset the board twice by double-clicking the button after it inserted to enter bootloader again.