Fluent when alone

Fluent when alone Idk how many peole have a similar sort of stutter and what this means in terms of the kind of stutter I actually have. So I have blocks, and it's always the first sound that is difficult to get out. Over the years I've tried things like taping my leg, prolonging sounds, etc. And yet, it's still the same :) But, the weird thing is when I'm alone I can speak fluently to myself. It's so frustrating and it's making me wonder if this translates to a confidence issue or an underlying psychological conditon. However, when I'm on the phone or a video call, the blocks come back. If anyone has had a similar experience, I'd like to know how you dealt with it (or are currently dealing with it), and what you learnt from it.