Because no one knows exactly what causes one to stutter, there can't be a universal "cure". Most likely there are many different causes of stuttering, whether physical or psychological. Anyone saying they have a cure is full of shit. Your stutter is probably different than mine, which is probably different from the next person. I've had mine mostly under control for decades, to the point where people I work with for years dont realize i stutter. Does that mean my methods will work for you? Possibly. Who knows? So, to answer your question directly, anyone claiming to know how to fix *your* stutter is a scammer. I personally would include speech therapists. I would be glad to share my methods that I feel helped my increased fluency. Not that I think it will stop your stutter, but it may give you an idea on how to craft your own journey.