Forgotten Username

hello, So it’s been months since I have had to change anything on my website… But now I do and I’ve completely forgotten my username but I’m almost 100% sure what my password is.
I have transaction proof from Hostgator that i’ve been paying for the website so it IS my website undoubtedly. I just need a way to contact someone about recovering my Username. I can’t access the area to edit my website.
P.S. I tried to recover password just to see if my Username would be somewhere in the email… and apparently my email doesn’t exist or is wrong. So I tried every single email I own and it did the same thing for each one. I’m extremely confused. I need serious help ?? ??
Thank you.