Apple India — need a new phone.

Address: Ludhiana, Punjab, 141001

My iphone 7. Just 4 months old.
Is having issue with display,
Battery
Ph turns
Off in between calls

Given ny phone to servixe centre 4-5 times.
But they updated software and said its ok.
But its still the same

After complainting again and again.
Service centre ppl said they will send ph to banglore and will change only display

But i need to replace my phone.
(Within warranty)

They are not ready to do that