Iphone keeps dying as soon as i take it off the charger

Hi,

Follow the instructions here > If your iPhone, iPad, or iPod touch won't turn on - Apple Support

What do i do because i never dropped my phone too hard ?

Too hard?

If you dropped your iPhone, there may be hardware damage.

If nothing in the link above helps, make an appointment at an Apple Store Genius Bar

Or an Apple Authorized Service Provider.

Help for your iPhone's warranty coverage see > https://checkcoverage.apple.com/

You need to check to see what is using the majority of your battery. Go to Settings>Battery, and see what app is consuming the majority of battery.

Also, you can go to the App Store and get an app called Battery Life and check on the status of the battery condition. It is similar to what Apple does to check on battery status.

If the battery is bad, there's nothing we can do with the software. Take it to an Apple Store or an authorized service provider so they can run tests and determine what alternatives exist.