My iphone 6 plus won't turn on?

I cracked my screen but it still worked perfectly fine. My dad changed the screen which caused it to not be able to turn on again? He switched my brother's battery into mine and it worked, but he took it off again and now it does not want to turn on. Any clue why? I'm frustrated

He could have damaged the battery connector when trying to replace it. He may have caused a short somewhere else. It's pointless speculating, if you want it fixed you will need to take it to an apple repairer

Send an email to Tim Cook and ask for a refund.

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