Ahh, I misunderstood! That’s unfortunate, I’m sorry someone just ripped your work like that :( in that case, the site admins would probably take it down if you could get in touch with them, at least off the front page. They might be willing or able to create a filter for your work so people can’t use it with the generator if they don’t modify it enough.

Unfortunately it’s something you’re going to have to actively watch for and reach out about because site owners are largely protected from the actions of their users by the DMCA, as long as they respond to such takedown requests from rightsholders expeditiously. This does mean that they’ll take any message you send them seriously though, and reaching out will show that your work is valuable enough to you that you’re willing to defend your copyrights.