I’m seeing the same problem.
Some attachments were rejected from the following WordPress.com Post by Email:
image.jpg – Unknown token
Its just HTML markup that the browser makes into a clickable thing for ex
<input type="tel" id="phone" name="phone" pattern="[0-9]{3}-[0-9]{3}-[0-9]{4}" required>
Try opening the CSV in excel, deleting any data you don’t need and re-saving as CSV. I have found this helpful to fix encoding type issues with CSV imports.
