Network Congestion Issue

[Icollectglass]

We upgraded to Xfinity TV a couple of weeks ago. Currently on 500 down/200 up package.  All good except today we noticed the TV freezing and slow wifi connection from a laptop less than 1 foot from the modem.  Ran tests through the Xfinity app and keep rebooting the Gateway modem.  I'm still getting poor results and less than 5 mb on the laptop.  Called Rogers and was told there is a node congestion issue. He would not elaborate if this is my home, my neighbourhood? Was provided a Case # and told to wait. Can someone please shed more light on what is happening here? Everything was fine until today! Currently unable to do any gaming from our Xbox or use the laptop.  TV freezing intermittently. What is node congestion and how can this be resolved?

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