If you have uploaded videos from Vimeo into a Video Gallery block and the thumbnails are displaying a "rainbow" of vertical lines (see screenshot below), it means that your Vimeo account has updated its API connection. When this connection is updated, it can sometimes prevent your video thumbnails from appearing on your website.

There are two options to fix this:

1. You can choose a custom thumbnail from your Image Library.
2. Re-add the video to the Video Gallery block, then delete the existing video.

Solution #1: Add a Custom Thumbnail

1. Navigate to the affected page within the CONTENT panel.
2. Scroll down until you reach the Video Gallery block containing the affected videos.
3. Click directly on the video thumbnail. Your Image Library will pop up. You can select an existing image from your library, or upload a brand new one.
   

Solution #2: Re-Add the Video

1. Navigate to the affected page within the CONTENT panel.
2. Scroll down until you reach the Video Gallery block containing the affected videos. Click on the "pencil" icon next to a video to open its settings.
3. On the pop-up that appears, highlight the Video URL, then COPY the URL. Close out the window.
   
4. At the top of the Video Gallery block, select Add Video. PASTE the URL that you copied into the empty field. The video, its correct thumbnail, and the Title and Description from Vimeo will populate.
   Note: Since the auto-populated Title and Description are populated directly from your video page on Vimeo, you can click the "pencil" icon to change them.
5. Finally, delete the video with the incorrect thumbnail by clicking the "trash can" icon beside it.