Problems countdown

Hello,
I’ve a countdown on the event page, but some users report that sometimes the countdown doesn’t indicate the correct time. I think maybe is a cache problem, before I had 12 of hours cache, now it’s only 2 hours.
I understand that if I create a event and I don’t modify it, the countdown should work fine, right?
If I modify the event, there may be problems, but now, some events that I’ve created I don’t modify and the time don’t correspond.

How can I fix it? I’m using wp-rocket, maybe if I indicate that don’t cache event pages?

The version of event single page template is 1.5
The verison of wp-rocket is 3.8.5
The version of Astra theme is 3.2.0
The version of WordPress is 5.7

Thanks

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