I had the same problem until I switched back to the original wall charger. Now I also purchased a fast dual car charger and it works like a champ. I hope this post will help you. Thank you
Also, make sure your charging port does not have any dirt or lint that sometime builds up in there. I have poked around the charger port and the headphone port with a small needle before and have taken out a bit of lint that was preventing g the cable from fully entering.
Not too rough, though. It is possible to mess something up if you push too hard or scratch up the charging port.