Thanks for the question, and welcome to Apple Support Communities. The following resource outlines network troubleshooting steps that may resolve your issue:
If the above solutions do not resolve the issue, try restarting your router / base station and Apple TV
1. Restart your base station or router. Sometimes this is done by turning the router off for a few seconds, and then on again, but check the documentation provided by the manufacturer.
2. To restart your Apple TV, press and hold Menu and Menu down/scroll (-) for about 6 seconds and then choose Restart from the menu.
Furthermore, you may want to check that specific ports used by Apple and external services are not blocked (for example, port 3689 might be operating as expected for AirPlay and iTunes Music Sharing, but others may not):