No display after replacing charger port

I have an iPhone 6s. It would only charge if I bent the lead so I ordered a replacement charger port. I stripped the phone and fitted the new part but now my phone won't turn on. Well, I think it's on because I hear alerts but nothing on the screen. I thought it may be a problem with the screen but nothing shows up in itunes either. If I hold home/power itunes then says it needs to update. I updated it and it says it would show after update/reboot but doesn't.