Chosen Solution
Tried to replace charging port and battery already.. Didn’t work. I can use it on iTunes and charge it on pc.. But outside of that, it won’t charge. Any thoughts?
Are you using an Apple original or MFi certified external charger? Does the charger you have work on other devices? Beyond the charger, the Lightning port and the battery, the only other thing involved with charging is the logic board but the fact that it does charge leads me to believe that is not issue. It is possible you’re replacement port is defective. However, I would focus on getting your hands on a known-good charger and cable (perhaps from a friend) and then try your phone with it. That will tell you if the problem is related to the phone or the charger. If it looks like a phone issue then you need to use known replacement parts. Sometimes dropping by a shop can really help out. They can try the parts without having to charge you for them.
