Why are there some comments I can't delete?

When trying to delete a comment, it's possible you're seeing the following error:

This means that CommentGuard can't delete your comment because Facebook returns this error when trying to delete it. It occurs for a small percentage of the comments we process every day. 

Sadly there isn't anything we can do to resolve this issue, because it's caused by a bug in Facebook's API. We found that this is a known issue that is acknowledged by Meta and which is reported often in Meta's developer forum. We're tracking the main bug report for updates.