Disable datepicker in suitecrm

Im creating a datefield that disables when Paid = Yes.
What i did I was able to disable only the input box through Javascript, and when the Paid = Yes, datepicker should be hidden. And the problem was hiding the datepicker wont work. Here’s my code:

if (invoiceStatus === "Closed Accepted") {
    if (paid == "yes") {
        document.getElementById('expected_pay_date').disabled = true;
       $('#expected_pay_date_trigger').hide();
    }
    else if (paid == "no") {
        document.getElementById('expected_pay_date').disabled = false;
        $('#expected_pay_date_trigger').show();
    }
}

try to debug you code like inserting values in text boxes, just to see if is working, and your code, you’re putting it where?

best regards