Hi, I'm Ashik. Welcome to JustAnswer. I'm reviewing your question now, and will post back with your reply ASAP
It is possible that the settings are corrupted, I'd recommend to reset it and then setup it as new Apple TV. Go to Settings > General > Reset. First try Reset All Settings.
After that, go to Settings > WiFi and connect to your WiFi network. Check if it is working now.
If not, then goto Settings > General > Reset and this time tap Restore. This will restore a fresh software on it. Then connect it to your WiFi network where your Macs are connected. Please let me know if that didn't work, so we can continue troubleshooting.