How to stop unexpected shutdown on iPhone 7

Have your battery replaced. If its too depleted, it may shut down when pressed for power and it cannot deliver it.

Check your Battery Health at Settings ➜ Battery ➜ Battery Health. If its less than 80% it needs to be replaced.

click here ➜ iPhone Battery Repair & Replacement - Apple Support

Check your battery's maximum capacity in Settings>Battery>Battery Health>Maximum capacity.

What percentage can you see there?

When was the last time that you had the battery replaced in the iPhone 7?

What is the current reading for Maximum Capacity on your battery?

Settings > Battery > Battery Health & Charging > Maximum Capacity.

Okancollins wrote:

Nigeria

You will need to contact Apple Support directly for battery replacement pricing in Nigeria.

click here ➜ Contact - Official Apple Support (NG)

Get an estimate here (after selecting your country):--> Choose Your Country or Region

From where? Apple has not sold the iPhone 7 since 2019. Its highly unlikely you could have bought a new iPhone 7 with a brand new battery in 2023, unless it had been replaced.

If it was replaced, and it was not done by Apple, it may say 100%, but there is no way to guarantee that is its actually at that capacity. more so, if its having unexpected shutdowns.