My battery health is decreasing very fast.
Battery health decreasing very fast
iPhone 12, iOS 15
User profile for user:
Community User
The battery becomes worn the more times it is charged over time. It's normal. You do not write how long you have used your iPhone, but if your battery has gone from 100% to 94% in a month, then something is wrong.
It is said that the battery needs to be replaced at around 83% so there is still plenty of capacity on your battery. If you still feel something is wrong, contact an Apple Authorized Service Provider.
Look here:
iPhone Repair - Official Apple Support
or
iPhone Battery Replacement - Official Apple Support
Read more about battery and performance here:
Batteries - Maximizing Performance - Apple