Please try the following troubleshooting tips:
- Power off you Apple TV, modem, and router for at least 60 seconds
- Make sure you're running up-to-date software
Visit Settings > General > Update to update your Apple TV's software (on 4th generation/tvOS models, visit Settings > System > Software updates
- Connect your device directly to the router via Ethernet cable.
- Disconnect other devices from your network.
You can also check with your Internet provider to see if your capabilities can be improved. If bandwidth is not an issue, then please click "contact us" on the link at the bottom of the page to fill out a ticket, which will send us a diagnostic report that we can use to help resolve the issue.