Xfinity is a very good service but I often see problems with it not being able to connect to the internet. For troubleshooting, you can use the application which you have to download to your device first. And after that do the troubleshooting steps described in this article https://howly.com/article/what-are-the-breakdowns-in-xfinity/ . There is this guide will help you to solve problems with this service.
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