unstable internet connection

I recently upgraded to the 1200 mbps plan and switched out my xfinity gateway. The internet is freezing every 2-3 minutes consistently throughout the day regardless of which device we are using. All tests on the app with Xfinity assistance show no issues but I believe I need to have a tech out. Unable to schedule a tech visit through the app or website at this time because according to the robots there are no issues detected. Need help with this please.