I used to have that problem too, but I don't now if it's gone or not because it's been a while I haven't been asked to say my name. But whenever I find myself in that kind of situation : I simply use my all time tactic : I take a deep breath before uttering a word in a gentle way so it doesn't look weird just like a normal breath and immediately I feel better and it works . Actually that breathing moment refreshes your brain and oxygen does his work and it helps reducing stress and anxiety witch would lead to more speech fluency . And , there is another thing that you should definitely try : imagine yourself talking to somebody over the phone and record that voice message and listen to it afterwards and spot the instances when you block or stutter and try to work on them( it might be a vowel or a consonant that you're not comfortable pronouncing , give that specific letter its chance and figure out how to make it more softer for you to utter). I hope that will help you.