7 year old doesn't like to be called by first name

Hello everyone. My almost 7 year old in the last year told me he doesn't like to be called by his first name. Which is Elijah.

We do call him Eli for short. I asked him why and he just said he likes Eli better.

Well Eli got tested and was put into special ed. He has known how to write Eli on all his work since kindergarden and he is now going into 2nd grade.

I'm wondering if he doesn't like his name because he has a hard time spelling Elijah or its because people don't know how to pronounce it like I do at home.

Has anyone had a simliar experience with your little not liking there full name?

I'm hoping he grows out of it.