That sounds a bit like one of my ex's, he had a habit of standing just inside ones personal space.
He did it with everyone Without even realising. But women especially will feel uncomfortable, other men may take it subconsciously as a challenge.Try not to stand square on to people especially if your forced to stand close to them and keep at least 2.5 3feet away.

Also do you stare people in the eyes when you talk to them? Eye contact is great intermittently but if someone is holding eye contact intensely it can be uncomfortable.

Lastly how do you speak to people? Do you keep a soft and even tone with plenty of spaces for interaction, or do you get anxious and maybe let yourself runaway with the conversation, talking at rather than too.

Even if it's none of these things specifically, it does sound like something in your body language that is being misunderstood.

All the best hope your able to sort it out.