I Can’t Even Say Their Names Right

So today, I messed up on 2 of my students’ names. I didn’t have their names wrong; I just don’t say them correctly. I don’t usually say someone’s name unless I’m sure what it is and I have never been corrected before, so this did come as a little surprise. And sadly, when one of my students was telling me how I say “Maxim” correctly, I heard no difference between what she said and what I say. And apparently the way I say “Nicu” is so funny, that Nicu couldn’t read the text when I called on him because he was laughing so hard, along with the rest of the class. I asked my partner teacher how I’m saying it wrong, and she said that I say it fine. I guess the students just like to have a laugh at the American.