On the top right side of your Yodeck Portal Main Menu, you will find a button that will be either:

Whenever you make changes within your Yodeck account, this button will turn orange and flash, saying, "Push to Screens". After you finish making all changes to your account, you need to push the button to deliver the affected players' changes. All Screens affected by your changes will download the required content and restart playback. Screens not affected by your changes will not be notified of the update.

Even if the button is black and has a "Changes pushed" message displayed, you might need to force a "push" to all Screens in your account. This might be required as a troubleshooting tool to ensure everything works as expected.

By clicking the black button, you will notify all Screens that they need to update content, and they will re-check and restart playback.