Occasionally, groups don't communicate well internally. Sometimes a link is posted on social to a website page before the page is "totally" ready. And maybe you end up with an image in that social post that has already been posted that was just meant to be a placeholder and not the real image. Or perhaps it's the "default" social image. Are you hosed since the post was already made? Do you have to pull it down and start over? You may have discovered that trying to post the link again even after you've updated the page does not necessarily show an updated image. This is because some social platforms such as LinkedIn cache a page's information after first usage for some period of time. So are you out of luck? If your post was made on LinkedIn, fortunately there is something you can do.
The Linkedin post inspector feature allows you not just to see how LinkedIn characterizes the metadata in a link to any website, it also refreshes the cache of that page that is used on LinkedIn. So if you replaced the social image used on the page (or if you didn't have one and just added it), running the post inspector will refresh the cache of that image used for all future and (most importantly), all existing posts that refer to that page.
Note, there are those who will wish to debate the value of posting a link in the original post vs having no link in the post and putting the link in the first comment, to which I will only say that LinkedIn updates its algorithm regularly, and the advice to separate an external link from the original post is years old. This discussion pertains to posting a link in the main post. The most important aspect of posting on LinkedIn these days is sharing "knowledge and advice" that drives meaningful interactions. So worrying about if the link should be in the post or not in the post sort of misses the main objective. Your posts should share something meaningful for your target audience and within your area of expertise.
Find the Post Inspector at https://www.linkedin.com/post-inspector/