Hi I'm asking about my iPhone. So Im the second owner of the phone and It still under warranty till 2024. So when I go to the nearest Apple store and said I want to replace my battery. They said okay but then they charged me for it. But when I searched online it says "if it's still under warranty then the replacement is free"
Battery replacement
Developers' forum is definitely the wrong place to ask. Contact Apple support instead. Good luck.