Iphone6 new battery iTunes and Google and phone system doesn’t work. I know the phone system is not support anymore I don’t use that for phone

iPhone 6 battery Replace and once it was replaced it came up and was working no problem and then all of a sudden it just went black and it just goes in the loop of showing Apple logo. I have gone into the laptop through iTunes and have reloaded to no avail and recovery.

I wish I would’ve just let the old battery alone. This is not my primary phone this is just for use for my tunes google etc