New Gateway issues

Background: We had an issue with WIFI dropping and Xifnity tech replaced line from house to box, changed out our gateway and then disconnected something in our attic (booster)?  we used same SSID and password and are have a terrible time getting devices to reconnect, especially our RING devices and Sprinkler system.

We have booster pods yet most devices are connecting directly to the Gateway and not the pods.

Question:  Troubleshooting is really hard given that I can't get accurate picture.

•  The XFINITY app will show devices as offline when they are connected.  My phone hasn't shown as online all day.  I'm using MacBook and it shows as offline device.
• Logged into the router and it shows devices as offline when I'm actually using them (MacBook, iPhone).

Any suggestions on how to get accurate picture of our system?

Thanks