Hello @michaelvauclare,
We can replicate this with the Event Category and Venues page where Rank Math cannot override the SEO title of the Event Calendar plugin.
Thanks to further explanation by @bart-2061

We have shared the issue with our developers and they are investigating it. As soon as we get some updates, we’ll let you know here.
@bart-2061, please open a new ticket here: https://support.rankmath.com/new-ticket/ and reference this so our developers can investigate the issue on your website.
We would appreciate your kind patience regarding this issue.
Please don’t hesitate to let us know if you have any other questions.
Thank you.
Hello,
We added a snippet named Ensures pre_get_document_title is called last with the filter pre_get_document_title assigned a lower(high) priority so it’s called last.
The the-events-calendar has this same filter, that’s overriding the title set by RankMath; we also tested other SEO plugins, and they behave the same for events taxonomies.
The code can be found at this gist; https://gist.github.com/Nickbahson/c58edbe25ea941a3223fde77b38e4a07
We apologize for any inconveniences that might have been caused by this issue.
Thank you.
Fantastic, this solution works for me.
Many thanks!
Wonderfull ! Issue fixed. Thank you so much
Hello,
We are super happy that this resolved your issue. If you have any other questions in the future, know that we are here to help you.
If you don’t mind me asking, could you please leave us a review (if you haven’t already) on
https://wordpress.org/support/plugin/seo-by-rank-math/reviews/#new-post
about your overall experience with Rank Math? We appreciate your time and patience.
If you do have another question in the future, please feel free to create a new forum topic, and it will be our pleasure to assist you again.
Thank you.