Hi @thaduri sai ,

try below code.

function onSubmit() {

    var requestedEndDate = g_form.getValue('end_date');
    var requestedStartDate = g_form.getValue('start_date');
  
    var format = g_user_date_time_format;

        var startDateMs = getDateFromFormat(requestedStartDate, format);
        var endDateMs = getDateFromFormat(requestedEndDate, format);

        if (startDateMs > endDateMs) {
            g_form.showFieldMsg('end_date', 'End date should be later than start date.', 'error');

            return false;

        }
    

}

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Runjay Patel - ServiceNow Solution Architect
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