sdfpubnix

You won't see them if lemmy.sdf.org started federating with lemmy.ml after you made those comments.

If you'd like to specifically import your comments, click the permalink icon on each comment you want from lemmy.ml's instance, then copy and paste said link into lemmy.sdf.org's search bar to import that comment.

For further reading, check out Lemmy's official documentation on importing comments.