If it is your own nanopublication, you can retract it or supersede it. A retraction is itself a small nanopublication, signed with the same identity, stating that the earlier one no longer stands. Superseding works the same way but additionally provides a corrected version that declares itself the successor of the old one. In both cases the original is not deleted — nanopublications are immutable — but services and user interfaces recognize the retraction or new version and act accordingly, for example by hiding the outdated one from listings. Tools like Nanodash offer this with a few clicks.

If the nanopublication is somebody else's, you cannot retract it, as retractions are only valid when signed with the same identity as the original. What you can do is publish your own nanopublication that comments on, disputes, or corrects the claim, which then becomes part of the public record alongside the original. You can also contact the author, who can then retract or supersede it themselves. This mirrors how corrections work in science generally: errors are not silently edited away, but addressed transparently and attributably.