Youtube Matic no sube la foto miniatura de wordpress

Hello, you buy a youtubematic plugin, the problem I'm having is that I want to publish the WordPress thumbnail photos on YouTube, I followed all the steps and the plugi doesn't publish the thumbnail photo on YouTube, here in the video I show the steps I follow to publish the entry with the thumbnail As I designed the configuration, I create the entry, then I send it to draft and then I publish it, but the photo is not published on YouTube. Note I don't know if it is public here or I can send you my purchase code and the access data to my WordPress or you have an email to send this information privately thanks Upload video to youtube custom photo does not upload: https://youtu.be/yLX_AxSKmsE Thank you