AC1200 won't connect with xfinity xb8 router

[gcwest007]

My old AC1200 worked fine with my older Xfinity router, but can't connect to my new XB8.  I've tried the WPS setup, Nighthawk app, website setup, and all the other recommended options, including add the MAC address into my XB8. After spending over 4 hours, I'm ready to ask for help.  For all I know, this old unit isn't even compatible with the newest routers.  I curse Xfinity for upgrading my router.  Advice?

[FURRYe38]

Might check to see if WPA3 security on the wifi is present. Older generation device don't like newer versions of WPA, even if they don't support it. 

[gcwest007]

That could be it.  The router has WPA3, but the connection to the Netgear only shows WPA2.  Sounds like I need a new extender.  Jim

[FURRYe38]

Try disabling security on the new router for temporary to see if the NG extender will connect at all. 
Re-enable after testing. 

Probably.