Why Do I Receive an 'Important Message' notification?

If your device is displaying an "Important Message" from Apple regarding your battery, display, or camera. For example: "Important Battery Message - Unable to verify this iPhone has a genuine Apple battery.” Don't worry, this is normal.

For iPhone 11 models and above you can see if the battery, display or camera have been replaced.

The “important message” will appear on the lock screen for 7 days, then appear in the settings for 14 days and will disappear after 30 days.