Easiest thing to do is a followup post correcting the wrong information.
We get this sort of question a lot where someone has posted incorrect information and asks to have the post deleted or the information corrected. If there's no replies, then it's an easy job. The difficulty comes when the post has been replied to and now it becomes a big deal to edit/delete the original and follow up posts. In this case, it's easier to leave the incorrect information and the poster can follow up with a corrective post.