Phone not charging until it is below 5% battery.

My phone not charging until it is below 5% battery when it's plugged, but it shows the charging symbol on the phone itself. It will start charging normally once the batter enters below 5% battery life (it will even reach 100%).

I tested it with an external battery that has an power monitor, and the phone draws 0Amps if I attempt charging at over 5%, and when I do it under 5% it draws around 1.4-1.5 Amps.

From what I read, I understand I could be either the charging PCB or the battery, what do you guys think it could be? Thanks in advance!