I can present in front of a class fluently without stuttering but speaking with people one on one I stutter

I can present in front of a class fluently without stuttering but speaking with people one on one I stutter Anyone else odd like this?? Like I can present in front of class when I have an assignment very easily, I don’t get nervous it’s like I’m prepared but speaking in general to people is somewhat difficult. I think it’s just the preparedness? What do you think, anyone else that has this too?