Bold formatting in Apple News shows HTML

I am struggling to have my bold formatting display correctly in Apple News when published by the plugin. I am using the latest version (1.30) of the plugin.

In recent days I have specified a theme and tried to find a setting that allows the formatting to work. The formatting is only on image titles and works OK on my site, however showing on each side of the image title (in bold!).

What can I change to make the HTML disappear?

The page I need help with: [log in to see the link]