You may see this message when trying to add a video to your Create Card:
The reason this happens is because the Mediavine Control Panel now requires each user to authenticate in order to access your Mediavine videos and get them added to the card.
Therefore, if you do get this message, it means that you're either not logged in to the MCP plugin, or, it can be solved by logging out and logging back in to the MCP plugin.
Please note: For this, you're logging in to the Mediavine Control Panel Plugin in Wordpress, not the Mediavine Dashboard.
Here's how to do that:
1. Go into your Wordpress admin and navigate to Plugins > Installed Plugins > Mediavine Control Panel > Settings.
2. Once there, you'll see "Authentication" right at the top of the page. From there, you will click to Login (or click Logout, then Login).
3. Go back into your Create card, and add the video. That's it!