I repair phones
回答“Why wont it turn on?”
If the screen is turning on and properly showing an image. The operating system could have crashed and is causing it to power cycle when turning on.
回答“Why does my phone fail to charge”
Maybe you should let them put the battery in it. Because like they said it is likely water damaged. Hopefully the bad battery wouldn’t have shorted out your charging port again.
回答“2012 Samsung Galaxy Note 10.1 with slow charging issue”
If you have done all the steps like changing battery and resetting. It seems more like a motherboard level issue instead of a battery / charging cable issue
回答“Screen won't turn on and won't stay turned on.”
Your LCD display most likely blacked out. It would need to be replaced then should be good as new as long as no other components were damaged you should be good.
回答“Why won’t my iPhone 7 Plus connect to the computer?”
Have you placed the phone in DFU mode?