Hi! I understand that your NETGEAR Nighthawk app is showing a "No Internet Connection" screen even though your internet is actually working. Let’s get to the bottom of this together.

To start, can you tell me if your device is connected to the Wi-Fi network broadcasted by your Nighthawk router? Also, are you able to browse the internet normally on that device outside of the app?

Meanwhile, here are some steps we can try that often resolve this type of issue:

1. Power Cycle Your Network
Unplug both your modem and your router from power. Wait about 2 minutes. Then plug in the modem first and wait an additional 2 minutes for it to fully connect. After that, plug in and power on your router. This refreshes their connection to your ISP and each other, which can clear up internet recognition issues in the app.

2. Check the App Permissions and Cache
Go to your Android Settings > Apps > Nighthawk app, and clear the cache. Also, confirm the app has the necessary permissions to access the network and storage on your device.

3. Make sure your app and router firmware are up to date
If you can, check for updates to the Nighthawk app in the Google Play Store. For firmware updates on the router, if you can't access them via the app, you might try logging in to the router's web interface via a browser at http://www.routerlogin.net or the router's IP address (commonly 192.168.1.1).

4. Reconnect the App to the Router
Sometimes the app may lose its connection with the router. Try logging out of the app, closing it completely, then reopen and login again.

If this doesn't fix it, please let me know the exact model of your Nighthawk router and any error messages you see aside from the no internet screen. That info will help me guide you further.

Are you okay to give these a try and tell me how it goes?