How do I add a new row in a table when I click on a button using Javascript [duplicate]

Hello all I am having a problem with my code. I want to add a new row with the same fields whenever I click on add product. However when I run the code and I click on add product it doesn't work.

Here's the HTML:

<table class="table" id="concierge">
<th>Item Name</th>
<th>Item Code</th>
<th>Description</th>
<th>Quantity</th>
<th>Price</th>
<th>Image</th>
<tr>
<td><input type="text" name="itemname" id="itemname" style="border: none"/></td>
<td><input type="text" name="itemcode" id="itemcode" style="width:50%; border:none"/></td>
<td><input type="text" name="description" id="description" style="border:none;"/></td>
<td><input type="text" name="quantity" id="quantity" style="width:50%; border: none"/></td>
<td><input type="text" name="price" id="price" style="width:50%; border: none"/></td>
<td><input type="file" name="image" id="image" style="border:none"></td>
<td><input type="checkbox" name="check" placeholder="Delete"></td>
</tr>
</table>
<input type="button" name="add" value="Add Product" onclick="addRow(concierge)"/>
<input type="button" name="delete" value="Delete Product" onclick="deleteRow(concierge)"/>

and the Script I am using for both Delete and Add:

function addRow(tableID) {

    var table = document.getElementById(tableID);

    var rowCount = table.rows.length;
    var row = table.insertRow(rowCount);

    var cell1 = row.insertCell(0);
    var element1 = document.createElement("input");
    element1.type = "text";
    element1.name="itemname";
    cell1.appendChild(element1);

    var cell2 = row.insertCell(1);
    var element2 = document.createElement("input");
    element2.type = "text";
    element2.name = "itemcode";
    cell3.appendChild(element2);

    var cell3 = row.insertCell(2);
    var element3 = document.createElement("input");
    element3.type = "text";
    element3.name = "description";
    cell3.appendChild(element3);

    var cell4 = row.insertCell(3);
    var element4 = document.createElement("input");
    element4.type = "text";
    element4.name = "quantity";
    cell4.appendChild(element4);

    var cell5 = row.insertCell(4);
    var element5 = document.createElement("input");
    element5.type = "text";
    element5.name = "price";
    cell5.appendChild(element5);

    var cell6 = row.insertCell(5);
    var element6 = document.createElement("input");
    element6.type = "file";
    element6.name = "image";
    cell6.appendChild(element6);

    var cell7 = row.insertCell(6);
    var element7 = document.createElement("input");
    element7.type = "checkbox";
    element7.name = "check";


}

function deleteRow(tableID) {
    try {
        var table = document.getElementById(tableID);
        var rowCount = table.rows.length;

        for(var i=0; i<rowCount; i++) {
            var row = table.rows[i];
            var chkbox = row.cells[0].childNodes[0];
            if(null != chkbox && true == chkbox.checked) {
                table.deleteRow(i);
                rowCount--;
                i--;
            }


        }
    }catch(e) {
        alert(e);
    }
}

Thank you in advance for your help