The Nos app supports delete of Notes. Sometimes a link or repost will not display correctly in the app you are using but it might look fine in another app.

If you post in your current app and decide you want to take something down you can log into Nos or other apps that support delete and remove the post. In the process you may discover that it looks fine elsewhere and there’s simply a rendering bug in the app you use. This is helpful feedback for people building the apps.