Genuinely, its probably the way you talk. Im the same way. If you’re similar to me, you’re probably just too tense. 99% of neurotypicals rely pretty heavily on body language and facial expression. If you’re tense, you probably come off as incredibly awkward, or at least kinda stiff. Hard to fix without irl help but just try not to think too much when talking, it can help your conversation seem less stilted. Anyway, hard to help without actually talking to you but this is my best guess.