Uncaught ReferenceError: changeQuantity is not defined

blade.php

<select onchange="changeQuantity(event, '{{ $cart['id'] }}')" class="form-select text-center" aria-label="">
    @foreach(range(1 , $product->inventory) as $item)
        <option value="{{ $item }}" {{  $cart['quantity'] == $item ? 'selected' : '' }}>
            {{ $item }}
        </option>
    @endforeach
</select>

js

<script>
    function changeQuantity(event, id , cartName = null) {
        //
        $.ajaxSetup({
            headers : {
                'X-CSRF-TOKEN' : document.head.querySelector('meta[name="csrf-token"]').content,
                'Content-Type' : 'application/json'
            }
        });

        //
        $.ajax({
            type : 'POST',
            url : '/fa/cart/quantity/change',
            data : JSON.stringify({
                id : id ,
                quantity : event.target.value,
                // cart : cartName,
                _method : 'patch'
            }),
            success : function(res) {
                location.reload();
            } 
        }); 
    }
</script>