Hello @RuthF73337 ,
Do you know if the video you're trying to link to was set to Private or Unlisted at any point before making it Public status? Are you getting a specific error message when trying to create the video block, or is it still inserting into the email but without the actual thumbnail?
If YouTube's API is unable to provide the thumbnail desired, or if there's an issue with importing the particular video link, then the best workaround would be to generate your own thumbnail image to link the video to. There's 3rd party sites and other programs that can be utilized to also add a play button overlay on your image, prior to uploading and inserting into your email.
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