Date displayed is December 31, 1969 on all

Hi Stephen, I’m new to our website and there is no runbook. Recently, after updates, the events on our website all reverted to showing the date for the event as December 31, 1969 at 7 pm. Unfortunately, I’m not even 100% that your plugin is being used (although I see it is installed and active). The agency that built the site locked down many of the normal WP functions, and theme and templates are managed via coded creation sFTP. Maybe you can make some suggestions as to what might be causing the date/time calendar issue? Already checked the server time. Thanks!

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