Iphone 6 corrupted battery argument?

I have an iphone 6 and it is a cool device. Recently, about a month ago, I noticed my phone died much quicker than normal and it got very, very hot. Even more recently my screen started popping off the side so I can see light on the inside. I was going to try to replace the battery but I figured I should take it to an apple store. Keep in mind it dies uncontrollably fast. When I was there they picked up my phone and immediatly saif I had a corrupted battery and that It can't be fixed. I asked why not and they said the battery can't be replaced because in the process it will most likely get pierced and destroy the device. At this point I have to buy a new phone, and I didn't buy a very expensive phone for the phone to have a defect and have to buy a new one. I couldnt help that it broke nor anyone else so why should I have to pay for a new one?

Sounds like youve received incorrect advice

unless the damage to the battery is the result of misuse by you

hopefully you hadnt dismantled it yourself

I would suggest you revisit the issue at the Apple store - which city btw?