Looks like there’s some caching going on, as this page 1, which forces TubePress to skip its internal cache, works normally. Are you using a WordPress caching plugin? If so, it might be caching the TubePress error shown here 2. We can safely say that your key is set up correctly, though it’s not clear to us why you were getting that error earlier.
Finally, the styling of the information below the video thumbnails (title, description, etc.) looks a little off due to some interference from your theme’s CSS. Please let us know if you need any guidance in resolving that issue.
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