jQuery: Regex to validate US postal doesn't work

With the code below, nothing seems to work. No alert message when I type non-numeric values in the Zipcode field. Please help me identify the issue.

$("input:text[name='address_1[zip]']").keyup(function(e) {
  var charCode = (e.which) ? e.which : event.keyCode
  if (String.fromCharCode(charCode).match(/^\d{5}(?:[-\s]\d{4})?$/)) {
    console.log("Please enter a number for zip code");
    $("input[name='address_1[zip]']").val("");
    return false;
  }
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.6.0/jquery.min.js"></script>

<input type="text" name="address_1[zip]" />

>Solution :

Your regex is about to only accept 5 digits for US ZIP and i have no idea about the rest of grouping regex : (?:[-\s]\d{4}) , it is not related to what you need.
and i corrected the code for you :

jQuery("input:text[name='address_1[zip]']").keyup(function(e) {
    //var charCode = (e.which) ? e.which : event.keyCode    
    // no needed!
    if (!$(this).val().match(/^\d{5}(?:[-\s]\d{4})?$/)) {
        alert("Please enter a number for zip code");
        jQuery("input[name='address_1[zip]']").val("");
        return false;                        
    }    
});