Why does my form only report "Multiple submissions are disabled for this form" error?

Recently, one of my JotForms has returned error messages (See Screen Shot). We use this particle JotForm so our employees can notify management of new work. In the past four days everybody that has attempted to use the JotForm has received the same error message (see screen shot). Do you have any suggestions on why this error is occurring?   

Hi,

That is because you enable Unique Submission to your form. Enabling Unique Submission will prevent users from making multiple submissions. Please check this guide on how to configure that: https://www.jotform.com/help/64-How-to-Set-Unique-Submissions-on-a-Form. You can disable that by selecting "No Check" from the option:

Thanks