Can someone relate, not being able to voice out a sentence because it starts with a certain letter?

Can someone relate, not being able to voice out a sentence because it starts with a certain letter? I struggle especially with letter A. And sometimes P T K. There are moments where I wanted to cry cuz my name's phonetic sound starts with A, and when people ask it, I get stuck like a goldfish out of water CUZ I CANT EVEN SPEAK MY NAME. Not even A-a-a-a. Just straight up "....." NOTHING. My mouth is open but I can't voice it out. So when I feel it coming, I use my nickname. Sometimes, I can speak it. So I'm really confused as to why this is happening. Can someone relate?