iPhone X connects to wiFi, but won't allow me on the Network.

I connect to my modem, enter the correct password, and hit "join". It check marks that I am connected. But when I try to use anything like Safari, It wont allow me to go anywhere but cox.com. When I enter my Username and Password (Which I know for a fact are correct because I can log-in fine on my Laptop), It says "incorrect username".