How to find someone who changed their username on Instagram?

[myself]

I was checking who unfollowed me on Instagram and I saw a bunch of people who did. However, some of them changed their username and unfollowed me. I tried to unfollow then but there was an error. Am I still following them and how could I unfollow them If I don't know their new user?

[Undercover Ninja]

You could type their name if you know it, not the username, into the search thingy. Or you could go to statigram.com and go to statistics, then it'll show you a list of everyone who unfollowed you, and if you see a blue arrow by their name, it means you're following them. Just click unfollow.