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I presume you are referring to the "Unique Submission" feature using "Check Cookies only"?
Unfortunately, there's no option that would set an expiration date on the cookies. Currently, the users need to clear their cookies or be in incognito/private browsing mode to bypass the restriction or to do multiple submissions. This option is also limited, let's say the user's browser configuration is set to not accept cookies or it auto clears it when closing the browser, then that will also bypass the restriction. To learn more about this, you can check this guide: https://www.jotform.com/help/64-How-to-Set-Unique-Submissions-on-a-Form
However, I will forward the option to set an expiration date on the cookie as a feature request to our developers. Note that I cannot guarantee that this will be implemented, but rest assure that they are aware of this request.