You’re right. It looks like it has Roswell as it’s own district, despite being a suburb of Atlanta (lol I’ve never been there, I had to Google it!)
It’s unfortunately not possible to make a new listing with Atlanta, but I wonder if you emailed email@example.com if they would be willing to ‘merge’ Roswell and some of the other suburbs in with Atlanta?
It’s like in Los Angeles, all of those cities like Glendale, Burbank, Marina Del Rey, Venice, etc all list when you search for ‘Los Angeles’.
It could be because Los Angeles is also the name of the county, but I think it would help your listing immensely if they could merge the suburbs in with “The Greater Atlanta Area” or something
Send them an email; Peerspace is pretty reasonable!