Is the image you shared from your device? Were you able to get the firmware version of your device? Is the device COM port detected on the device manager? Have you tried a different USB cable? Can you try power it on then scan with nRF Connect mobile app?
That’s strange. Your unit seems not have the RAK default firmware.
Since nRF Connect cant detect it, then you can only update the firmware by programming the nRF chip. One why is by using RAKDAP1 - RAKwireless Documentation Center