I am not sure I understand what you mean.

You're saying that you added exactly this link description in a previous link post and it was reused in this post? Maybe the value does not get automatically deleted in the text input box so it will still be used for the next link if you don't delete it manually.

Or do you really mean a link comment?

I haven't found a duplicate comment or a previous link with the same description in your history though. So can you give examples with links (linking to the duplicate comments / descriptions)?