You can try blowing it out with one of those air blowers that photographers use remove dust from a camera sensor. It's not canned air, the air pressure is no more than how hard you can squeeze. The usually have a soft brush attachment too.
This also might be worth a try if you haven't tried already
Whilst phone is on plug charger in and restart phone with charger still plugged in. It's just that I kept getting the 'Moisture in port' message although there was no moisture in port. Tried everything from cotton buds to hairdryer but nothing worked. Went to samsung website and many people had same issue but by doing what I said above worked. Never had issue since.
I had the same problem and changed the charging cable. Same problem. Went to have it repaired and they pulled a ball of lint out of the charging port. Works perfect now.