Normally this happens when the YouTube account you connected on SocialBook is not the one you currently logged in on YouTube:
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To fix this, please follow the following steps:
Step 1:
First make sure you have SocialBook Builder installed: https://socialbook.io/help/socialbook-youtube-builder-manual/
Step 2:
Go to https://socialbook.io/connect_socialmedia and make note of the channel you connected:
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Step 3:
Now go to https://www.youtube.com, click on the top right corner your avatar, and make sure the one you logged in is the same channel as the one you connected on SocialBook:
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Step 4:
If they do not match, you can switch to the connected channel from YouTube:
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Once the channel matches, you should see the loading button on the right side:
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and you can click to see the video stats now.