To be completely honest, the fear of stuttering is waaay worse than stuttering itself =) Congratulations to you! BUT! now you've had this victory, you must persevere. You must keep calling people on the phone. Keep that confidence and keep boosting it. Everytime you stutter, think about that one positive experience you had and take your time. A fun challenge would be to call someone every single day. just one. Doesn't even have to be that important.Call the local drug store how much they have left of a certain medicine, call your mother, call your best friend or colleagues to tell them what you've otherwise send them a text or mail for. Join the discord group and start dipping your toe into talking with strangers. Ask a random guy on the street how to find the nearby supermarket. Doesnt matter. but keep boosting that confidence! You've already taken the biggest hurdle, all you gotta do is jump the smaller ones from now on!