place on chin won't clear up

I have had this place on  my chin that will not clear up for like 4 months straight now. I went to a dermatologist she put me on some antibiotic that I ended up being allergic to. I took the meds for nearly 5 weeks with no help for my chin seen. After 5 weeks I broke out in a serious case of hives, my doctor said I was allergic to the antibotic (antibiotic) he gave me a steroid shot that day as well as a 7 day steroid pack. By the end of the week of taking the steroids the place on  my chin was nearly gone! The very next week it started to come back again.

It is not acne, it is a huge patch of bumps that end up scabbing over, there is no white head or black head in them that you can tell. Why would the steroids help it? Does anyone have any idea what it could be?

Please help