I had this a while ago, I was advised to buy some dissolvable aspirin and add a tiny amount (just enough to dissolve one tablet) of hot water from the tap (not boiling) then wait for the tablet to dissolve completely, in which time the water will have cooled down slightly. Then use the dissolved asprin and a cotton bud stick to clean both the top and bottom of the piercing once a day. This worked really quickly for me and the lump was gone within a few days.