My device xperiaz5 getting very hot battery draining fast

[DePope]

I have XperiaZ5 from 3Network, been using it for over two years now. Recently it gets very hot even on call. I have restarted and reset the phone problem persists. Any idea what might be the cause?

[Uliwooly]

@DePope

The more  you use the phone the hotter it'll get, also, since the phone it's more than 2 years older the battery won't hold charge as much as it used to 

[DePope]

Please can my phone battery be changed and how much will it cost.

[gusferlizi]

Back-up your data ASAP! This is a design flaw. Replacing the battery will not fix it.

The phone structure is too flexible (terrible engineering) and eventually the motherboard/cpu inside breaks and goes into a partial short-circuit.