Everyone has a blind spot. The difference is whether you let anyone tell you where it is.

A blind spot is by definition something you cannot find alone. No amount of reflection reveals it, because the instrument doing the looking is the thing with the gap. The only route in is another person, which means the deciding factor is not how self-aware you are but how safe you make it to tell you something.

Ask one person who has seen you up close for a while. Give them an easy question: what is one thing I do that I probably do not notice. Then do nothing but listen, and thank them, whatever it is.