Battery health not showing properly in iPhone
When going into settings -> battery -> battery health. It's stuck on the loading screen and doesn't properly display the battery.
[Re-Titled by Moderator]
iPhone 16 Pro Max, iOS 18
When going into settings -> battery -> battery health. It's stuck on the loading screen and doesn't properly display the battery.
[Re-Titled by Moderator]
iPhone 16 Pro Max, iOS 18
If your iPhone has a history of Camera/Battery/Screen replacement/ Repair/Service from an un-authorised service provider then the only option that you have is to take the device to...
Take your device to an Apple Retail Store or Apple Authorized Service Provider, or contact Apple Support:
Find Locations - Location Selector - Apple
Contact Apple for support and service - Apple Support
Get a Genius Bar Reservation and Apple Support Options - Apple
Contact Genius Bar.
Manage Reservations - My Reservations - Apple

Parts and service history
With iOS 15.2 and later and iPhone XR, iPhone XS models, and later—including iPhone SE (2nd and 3rd generation)—you can go to Settings > General > About for the parts and service history of your iPhone. You can also find out if the battery has been replaced. If the replacement was done using genuine Apple parts and processes, "Genuine Apple Part" will appear next to Battery.

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Battery health not showing properly in iPhone