Help with link previews on POST request

I have no problem geting previews when posting lins via desktop, web or mobile.
I’m trying to create an n8n automation so that when a new post is created in a public channel then the link to this new post is posted in a private channel along with some more private information. Then the link to the newly private post is posted back as comment in the initial public post. The result is a coment with a preview of private information available only for the members of that given private channel. This works fine by doing it manually but
in terms of automation all posts are created, but I havent found the way for the previews to be generated either automatically or manually as attachment or metadata.
Any help please?

Welcome back to the forums, Cesar! And thank you for the detailed report. This sounds like a really cool use case! Since link previews work when posting manually but not through automation, it may help to ensure the EnableLinkPreviews config setting is enabled on your server. Also, link previews are only generated if the server can access the linked URL - can your Mattermost server access the private post URL you’re including?

Yes, the private links are accesible, since are made from my user account.