Cant find usernames and emails

5 times, I have received this message below and I can’t find the username or email addressess that gets copied with this below email. I can’t even find the username. Why do you think in addition to my email, a few email addressess are being sent this email? Have I been hacked? I don’t even find the submission listing? Or is someone forwarding all my site activity into their end? I had used a Freelancer before from India and he decided not to finish my site. I did not upload the site that was a backed-up but I went back two weeks before he worked on my site and uploaded it. I hope I have not been hacked! How can I solve this problem? I want to remove those email addresses above, but I can’t find them in my site.

Here’s the email content:

To: myownsite, ckfawo@sonamn.com, rettavan@hotmail.com, trepsimpdadist1982@yandex.ru, vittorinifs@hotmail.com

Hello jxovlbclq,

Thank you for adding a listing. Please do not omit to visit our home site for more site features > Kind Regards Management