Hello Eileen,
I hope you're doing well!
You can restore the countdown display by going to Site Designer, adding the Countdown widget, and then publishing the changes. It appears that the countdown previously shown on the Home navigation item may have been removed, but adding the widget will bring back the days-until-event display.
For additional information, please refer to this article: What is the Countdown Timer widget counting down to?
Please let me know if this helps or if you have any further questions. I'm happy to assist.
Best regards,
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Sanjog Rana
Subject Matter Expert
Cvent Client Services
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