AC750 model R6020. Can’t connect router to Apartment WiFi.

I live in an apartment that provides WiFi as a part of the rent. It’s a public network and you have to log in to a portal and add the MAC addresses of the devices you want to use. So I’m trying to add the router but running into an issue when I try to connect it. I have it connect to the Ethernet port in my room and I added the MAC address but it still refuses to connect. Any ideas?

Edit: I should also add that I know it’s possible to set up a router here because when I look at the WiFi networks there’s tons of them around me