I Got My Belly Pierced About 5 Months Ago I

I got my belly pierced about 5 months ago i changed the ring last month and the piercer said it was fine 2 weeks ago i noticed a blister of blood. I took the ring out cleaned it and put the ring back in. Last week i looked at it again and i was filled with pus i drained it and kept cleaning it today i noticed it was filled with pus so i drained it again. What do i do?