Page not eligible for rich results known by this test

Hi there!

As advised in your https://rankmath.com/kb/rich-snippets/ page, I’ve checked some of my posts in the Google Rich Snippet Testing Tool.

Although the old and soon deprecated version (Structured data testing tool) doesn’t show any issue
• http://sebimessinaphotography.com/underwater-wedding-photography/
• Blog Posting 0 Issue 0 Warnings
• https://sebimessinaphotography.com/portfolios/weddings/
• Detected 0 Erros – 0 Warnings 0 Items
if I move to the Rich Result Test I get “Page not eligible for rich results known by this test”

Amusingly Posts and Portfolios do not pass the test, while most pages do.
• http://sebimessinaphotography.com/
• Page is eligible for rich results

 This happens only on my main domain https://sebimessinaphotography.com/ where Rank Math has been installed a couple of days ago.
 If I test other sites/subdomains like https://www.trashthedressunderwater.com/trash-the-dress-underwater-images-andy-and-christian/ I get “Page is eligible for rich results”

You can take a look, please?

Thank you in advance for your time

Sebi