What Causes Persistent Itchy Rash Near Groin?

hey, i am a 16 year old guy and suffer from something(i researched) from jock itch near the butt and the groin..it started around a year ago..as soon as i found out that it was a fungal infection i applied a cream called candiderma regularly..i managed to stop the itching and peeling off of the skin for some time.although the stain remained, now it has all started again...please help as itching all the time is a quite embaressing...