WOrdpress SEO Yoast – Focus Keyword not recognised in Title

I have the Yoast plugin on WordPress site (www.rosewarnegardens.com) with Pagelines theme. On running the SEO check on each page it says Focus keywords are not listed in recognised e.g for this page:
https://www.rosewarnegardens.com/what-do-we-do/commercial/architect/

the following is reported in SEO page analysis:
-The keyword / phrase architects does not appear in the page title.
YES IT DOES, THIS IS THE TITLE OF THE PAGE

-You have not used your keyword / keyphrase in any subheading (such as an H2) in your copy.
YES IT IS USED TWICE AS A SUBHEADING ONCE H2, ONCE H4

-The keyword density is 0%, which is a bit low, the keyword was found 0 times.
THE KEYWORD APPEARS 3 TIMES IN THE CONTENT AND HEADINGS. WHICH WORKS OUT AT APPROX 2%

Obviously it’s something I am doing but WHAT?!