Collection Canonical URL (Dynamic) Troubleshooting

Hi all!
I need to add a canonical URL to some pages in a collection (republishing a Substack). I followed some posts here to (1) Add <link rel=“canonical” href=“[canonical field]”> to the custom code in the header of the collection and (2) Add a text field to the page editor to pull the canonical url.

Looks ok to me when viewing page source, but no tools are catching it :confused: Any help is appreciated :slight_smile:

Page: Before There Was Money | EOM #002
Canonical URL: Before There Was Money - by wotterdog - Evolution of Money

Here is my site Read-Only: LINK
(how to share your site Read-Only link)