My battery is having problems

It seems that the battery you have installed in your iPhone is not original. It is not possible to see Battery Health on non-original batteries.

You can find more information here:

About genuine iPhone batteries - Apple Support

The real problem is that the wrong battery was installed in your phone. If you had a shop perform the service, go back and get your money back.

Take the phone to an Apple Store or authorized Apple Service shop so that the correct battery can be installed. About $70 U.S.

Apple Authorized Service Providershttps://locate.apple.com › ...