Wi-Fi extender pod connection issues

I have a new gateway XB8 router which I obtained because my WiFi extenders stopped working with my old gateway (which was otherwise working fine).  I couldn’t connect the old ones to the gateway and it would time out while trying to connect.  Since getting the new gateway (which was suggested by an Xfinity agent after 1.5 hours of troubleshooting), the same issue has arisen.  The Xfinity app will recognize the new pod and add it to “my equipment” but will not connect to the internet.  I’ve tried recycling the gateway, unplugging and replugging the pods and doing them one at a time, bought a new pod and it won’t connect either.  Any ideas?  I have checked the security setting is the right one as well.  I am at a loss.