Datepicker is one day off on published site

I’ve hooked up a datepicker with Finsweet so that users can pick a date for events they’re looking for. The integration works fine but for some reason the date is always a day off - e.g. I put October 8th on the calendar and events for October 7th appear in the list. I know my timezone is accurate, so I’m pretty confused as to how this is happening. Any help would be super appreciated!

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