Diablo Immortal Error - Unable to Authenticate with Battle.net

Before trying any of the following steps check the BlizzardCS Twitter for any service interruptions.

If no errors are reported there, try the following troubleshooting steps;

1. Make sure the app is up to date
2. Try swapping from wireless to your network data connection, or vice versa
3. Restart your device and try again
4. Make sure that your device meets the minimum requirements to run Diablo Immortal.
5. If you are on an Android device, access your app storage in device settings and clear the Diablo Immortal app cache/data
6. If the problem persists, uninstall and reinstall the game