yes, absolutely there are cases that last longer than 24 months. They include:
Pluckers, especially pluckers that do not give up the habit completely. Every plucked hair will return, but we dont know when this may happen.
Cases who do not get enough treatment or who stop part way through. You need to be clearing all the visible hairs.
Cases who continue to shave throughout their treatment.Shaving prevents us from treating up to 2/3 of the hair that we could have otherwise destroyed.
And finally, cases where there are hormonal influences that are not addressed medically. This is a possibility with undiagnosed or treated polycystic ovarian Syndrome, . In such cases the high androgen levels ( which areregularly reduced with spironolactone such as in your case) . Refuse to get medical help in this way, and you can have a life long hair problem.
Happily, I dont see any evidence of these issues with you, so you should have good success.Just be patient.
Seana