Internet will not connect

What model gateway do you have, and what lights are showing? If you're seeing red Broadband and/or Service lights, you likely have a broken connection at some point. Of course, make sure that the data cable connecting your gateway to the wall data jack is connected and undamaged.

I suggest that you download and install AT&T's Smart Home Manager from your app store (Apple App Store or Google Play). It's a free tool and will help you identify if there are issues with your service, allow you to run a speed test directly from the gateway, determine if you have good Wi-Fi performance throughout your home, etc. The tool can also schedule a service call, if indicated. If this doesn't help, you'll have to contact 800.288.2020 for service and be prepared for long wait times.