Child Having Ring Worm On Back Of Neck Right Below Hairline, Took Cap, No Relief, White Heads Forming. Cure?

My daughter is 7 yrs old. When she was 6, she got what appeared to be a ring worm on the back of her neck right below her hairline. She recieved a topical cream, in addition to an oral medication she had to take for 6 weeks. I took her back to the doctor in November, and they gave her another oral medication that was a little stronger for 6 more weeks. This oral medication doesn't seem to do anything to my daughters rash to make it disappear. In January I began to use Blue Star which took it away for a while, but then it just became raised again after a few days of not using it. Now, the blue star doesn't help at all. I have also used Vaseline and coconut oil, but the rash does well for a few days and then just becomes irritated. This week I decided to try and dry it out, now little white heads are forming. What is this?? It has never spread into her actual scalp.