I have the same problem with my Reolink RLC-520 cameras.

When I select the Reolink brand it auto fills a Stream URL of: /cgi-bin/api.cgi?cmd=Snap&channel=0&rs=w&user={0}&password={1}

I have tried this with both port 80 and 443 with the user and password entered. Neither work.

If I put the following stream URL in Firefox, it pulls up a single image of the camera: http://192.168.1.112/cgi-bin/api.cgi?cmd=Snap&channel=0&rs=w&user=guest&password=accesscamera (IP, user, and password changed to generic values)

Is "Snap" the correct API command for video?

I can access the cameras via VLC using: rtsp://guest:accesscamera@192.168.1.112/h264Preview_01_sub

I tried putting the above rtsp in the stream URL with port 554 without success.

Any other suggestions?