How do I fix Battery Indicator/Restart Loop

Back in March I replaced the battery and lightning jack. All the screws are in the correct place and all the seat for connections are good. The battery and phone have worked great so far... but starting on 6/18/18 I went to charge my phone while it was at 33%. I plugged it in and left it. I came back maybe 30 min later and the phone still said 33%....I knew that wasn't right. I figured maybe a fluke and left it to charge for about 2 hours. Still at 33%. I took it off the charger and turned it off and turned it on. Back to 100%. However, after some heavy use the battery indicator didn't change, so turned it off and on and it changed. the following day (Monday) the phone would get stuck in a restart loop.

Since then the restart loop continues off and on and the battery indicator still does not work. I have tried the following:

- Hard Resets

-DFU Reset

-SIM card replacement

I am getting a new battery in the mail and intend to do another battery replacement, but do not think it will solve the problem. Maybe a new lightning jack? or good deep clean of the port? Funny thing is it charges and appears to work fine besides getting stuck in the restart loop and the battery indicator being inaccurate.... any thoughts?