My iPhone battery keeps bringing unknown part why

Did you replace the battery in this iPhone recently? If so, was the replacement done by Apple or an Apple Authorized Service Provider ... or did you use a third-party repair outfit?

Which exact model is your iPhone?

Usually you will not get the Maximum Battery percentage when the battery has been replaced with a non-Apple battery. If that is the case, the message you are seeing will not go away.

Have you had the battery replaced or purchased the device used?

Then you need to take it back to them to get this resolved.

You can also check to see if they are an Authorized service provider by going here:

• Repair Provider Verification - Official Apple Support

Based on what you provided, whomever you went to either did you use genuine Apple parts or did not perform any repairs properly. This would be typical of a third-party repair shop as they cannot get genuine Apple parts to make any repairs, including replacing the iPhone's battery.

Again, you need to take it back to them.

Take it back to where it was serviced, since it was not done correctly. Luckily all service performed by Apple Service providers come with a warranty.