MacBook Pro 13" 2022 - it won't start

Hi All,

Some time ago my 2022 Macbook Pro 13" abruptly stop working, it simply turned off itself.

Needless to say I tried every keyboard combination, I took it to an Apple shop and they said they would need to send it for repair, and it would cost $600 "flat fee".

I then decided to give it a try, I ordered a new battery from ifixit and replaced it, following the instructions.

But when I plugged the power cable in, still nothing.

Can anybody tell me what could the problem be?

Thanks!