AX1800 EAX20 Extender Suddenly Not Providing Internet Access

[btesnar15799]

I purchased the AX1800 EAX20 WiFi extender in June 2021.  It worked well for three months and then suddently stopped working (providing internet access).  I reinstalled/resetup, etc, and nothing works.  It is connecting to an xFinity Gateway device model CGM4331COM.

[plemans]

Are you setting it up using the installation assistant or using WPS (push button) method of install? 

What firmware is on the extender? 

What error is it giving you?