JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://ajax.aspnetcdn.com/ajax/jquery.validate/1.10.0/jquery.validate.min.js"></script>
<form id="myform">
        <select id="id_deals-0-currency" name="deals-0-currency">
        <option value="">---------</option>
        <option value="1">USD - $</option>
        <option value="2">EUR - €</option>
        </select><br><br>
<input type="submit" value="Submit"/>
    </form>

JavaScript

$(function() {
    $(document).ready(function() {

        $.validator.addMethod("valueNotEquals", function(value, element, arg) {
            return arg != value;
        }, "Value must not equal arg.");
        
        $('#id_deals-0-currency').change(function(){
            $(this).valid()
        })


        $("#myform").validate({
            debug: true,
            rules: {

                'deals-0-currency': {
                    valueNotEquals: ""
                }
            },
            messages: {

                'deals-0-currency': {
                    valueNotEquals: "Please select an item!"
                }
            }

        });
    });
})