Happened to when I had a connecting from New York. I was traveling from Canada. The immigration officer asked me a question and I stuttered bad but I kept a mask on so no one could see my stupid face. She asked me what's wrong why ain't you answering? I said I have a stutter. She said can you see the line behind you we ain't got all day and that made me more nervous. Ain't letting you down already but that's what happened with me. Eventually answered all her questions.