I'm rather shocked at the lack of a solution for this. I've had the same issue for atleast 8 months but never felt the need to fix it because normal charge worked just fine. But curiosity got the better of me and I looked up the posts and found 0 actual solutions to getting fast charge working again. If your here then no drrr we know to check the cable and charger box. Chances are it didnt fix the issue. Drrr we all know to clean the port. Again chances are that didnt fix the issue. So without anything further here is the solution. During one of the updates the battery calibration was messed up. The fix! Recalibrate the battery rooted or none rooted. It's rather simple. Go to Google play and download advanced battery calibrator. Follow the instructions. Turn your phone off. Fully charge it and turn it back on. Now when you plug it in you will see fast charging. Took all of 5 minutes to figure this out. Shame on you Samsung "technical" support. This will also help if you experience weird battery drain issues. You can even go into your phones recovery and clear your batteries cache and reboot. Updates always seem to mess up something little.