AMP issue / Server error (5xx)

Hi SI Team

I am getting errors from Google Search Console

Search Console has identified that your site is affected by 1 new AMP related issue. This means that AMP may be negatively affected in Google Search results. We encourage you to fix this issue.

The URL in question seems to be this here:

https://finalbug.net/index.php/blog-final-cut-training-resolve-etc/entry/fcpx-media-foundations-part-02

Which when I look at it in a browser I see the following....

Viewing An Unpublished Post
You are currently viewing an unpublished post because you are a site admin or a moderator.

The thing is that when I see the above I am not logged in as an administrator.

In the top right hand side of Google Search Console I see the following.

https://finalbug.net/index.php/blog-final-cut-training-resolve-etc/entry/fcpx-media-foundations-part-02?format=amp

Canonical version: https://www.finalbug.net/index.php/blog-final-cut-training-resolve-etc/entry/fcpx-media-foundations-part-02

Honestly this is over my head but if I had to guess I would say that this post is published and not published at the same time and that this is confusing Google.

kindly advise

Paul