My whole life till now

My whole life till now Since my childhood I have stammering(I can speak all letters but I repeat words).Due to this i have gone through all negative comments in my childhood and bullied. And now I am 22 years old ,I have realized that when I am talking to girls I speak very slowly and in a base voice by this I can speak 98% fluently with out stammering. And managing stress and dietary habits also imapacts.By practicing it improves but it takes lot of times.Recently i have seen some companys claiming that they will cure stammering permanently.I cant talk to only girls rest of my life right and I am taking that does it really work or this is a scam?