Consult a Surgeon
As mentioned already, a hair transplant could be a viable "next step." It's vital to consult a physician for a diagnosis and recommendation first, however, to see if you are a candidate.
Hairline changes since childhood
There is a large variation in hairline patterns among males and females.
In general, if a hairline has been a certain way since childhood, it is unlikely to respond to any specific treatment. The only way to alter the hairline woul be via a hair transplant.