I'm sorry about the issue. What's the model of your new Arris modem/router device?
Do not type / enter your network name. Normally, it should show your network name automatically.
When you go to the Wireless LAN setup menu on the printer's screen, does it show a list of network name(s), including yours? If yes, what happens when you select / connect to your network name? Does it ask for password/passphrase?
Do you have windows xp, vista, or 7, or 8, 10, or mac computer?
Please reply at the box below. Thank you,