AC797S Port Forwarding - Range of ports

Folks, I've been trying to set up port forwarding on my AC797S (That's my Unite Express 2 hotspot from AT&T) for my Nintendo Switch. The documentation says it can be done, but what I DON'T see is how to enter a range of ports. The UI looks like this:

I can enter A port, but entering 45000-45001, for example, failed with "Error adding entry". Is there a special syntax for a range of ports? I would like to forward 45000-65535, so adding all of them is obviously not an option.

Any suggestions or solutions would be greatly appreciated. Thank you!