Trying to filter out non business emails from our Form Submission

Hello! I am trying to figure out how to block form submissions from nonbusiness emails ( EX:,, etc.). I was able to find an article on here that led me to this code

<script type="text/javascript">
    $(document).ready(function(e) {
        $('#submit-button-id').click(function() {
            var email = $('#email-3').val();
            var reg = /^([\w-\.]+@(?!!!!!!!!!!!!!![\w-]+\.)+[\w-]{2,4})?$/;
            if (reg.test(email)) {
                return 0;
            } else {
                alert('Please Enter Business Email Address');
                return false;

That works… kind of, it blocks EVERY email. I am about 4 years removed from my last HTML/Javascript/jquery class, so I can follow along with most of the guides I have seen but this one has me pretty stumped.

Any and all help is welcome thank you!

Heres the read-only link: Amify Website Read Only Link