1. Check if the network is active and within range.
2. Look for any login page or authentication step on your device and try to re-enter the credentials.
3. Reboot your device to clear any cached connections.
4. Re-check the WiFi connection settings and double check the password if necessary.
5. Try and connect to the network from another device.
6. Check if the network is working on other devices.
7. If all else fails, contact the network administrator to see if there are any network issues.