Why is my iPhone SE turning on/off after a battery replacement?

Update: After opening up the iPhone. Reconnecting the logic board/battery I was able to get the iPhone to turn back on. I'll use Activator to lock my phone for now. I'm going to replace the Lock Button cable later to see if it will fix the issue.

Hi, so I recently replaced my iPhone battery with a new one. And my phone worked fine after a couple of days. But today my Lock Button stopped working. I’m jailbroken and one of my tweaks asks for my fingerprint every time I try to turn off the device and the prompt kept coming up even though I never tried to turn off my phone.

So I rebooted the iPhone and now its turning on/off non-stop. (Apple logo appears then shuts off and then reappears)

Any solution?