New user: failure/API error (Preview)

Hi,

I’m a new user and added the plugin after about 650 posts to my blog. I receive the following errors when I try to publish the most recent post (linked). The result is that nothing is published. I’m using the latest WP and plugin versions.

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The following components are unsupported by Apple News and were removed: div

There has been an error with the API: ONLY_PREVIEW_ALLOWED
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I don’t understand the API error. I’ve tried re-entering my keys and nothing has changed. I have a debug email but I can’t make sense of what the issue is.

My settings:
Post types: Posts; Alerts: warn; Image settings: Remote & Full-bleed = yes, Cover Art = no; Format: HTML support = yes

Any thoughts? Many thanks for your help,
M

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