Here are some things to try:

1. Check your Wi-Fi signal strength. Make sure it’s strong enough to connect.
2. Restart your device. Sometimes restarting the device can reset the way the connection behaves.
3. Check your Wi-Fi password. Make sure it is entered into the device correctly.
4. Reboot your router. It may be helpful to disconnect the router from the internet for a few minutes and then turn it back on.