Yes, I am using the title variable in the SEO title.
I am having the same issues. Yoast 19.3 reported that the keyphrase is not in the SEO title when it was. At the time, it showed red for keyphrase in the SEO title. Then I filled in the meta description and it showed orange for keyphrase in the SEO title, just not at the beginning (it was at the beginning of the SEO title, but not at the beginning of the meta description). Looks like a bug to me.
Thank you so much for the prompt reply, André. I disabled the caching and the data was shown properly. However, when I re-enabled it, the data disappeared again.
Regards,
Gary