Just installed new Xfinity router; my laptop now recognizes new WiFi network but I can’t connect to internet; anyone know a solution that might relate to my hardware properties?

 extensive time spent with escalated cust. svc; still no solution; a new router was mailed to us by Xfinity with instructions on how to set it up. Before the new router arrived, Xfinity sent us a letter stating they needed to correct an "identified problem." Router arrived, we followed instructions to hook up the router. Wondering if problem could be related to settings on my laptop. Anyone know a solution?