My battery health is degraded
my iPhone battery is always draining every day.
iPhone 6s, iOS 15
This means that your iPhone's battery is reaching the critical point of its life, and could have unpredictable behavior, including the fact that it may suddenly stop working.
I suggest that you start creating a full backup of your iPhone on a regular basis (at least once a week), and have your battery replaced as soon as possible. See this support page (about prices and other instructions), selecting your country:--> Choose Your Country or Region .
Then make an appointment (*) and have your device serviced at an Apple Store or AASP (Apple Authorized Service Provider) among this list:--> https://locate.apple.com/choose-country-region .
Regards
Giulio
(*) You can do it:
- Online:--> Genius Bar Reservation and Apple Support Options - Apple;
- Contacting a local Apple Store or AASP among the list provided above;
- Using the "Apple Store" app, available and downloadable from AppStore.