Updating Qty of All Line Items on Cart page

Technical Q&A
1

When I go to update the QTY (plus or minus) of one line item on the cart page - it is updating the QTY of ALL line items instead of just the one I selected. Is there an issue with my code. I do have a wholesale plugin so apologies for the lengthly code.

The cart.liquid code


{% render 'wc_cart' %}

The cart-item.liquid code


    

      
    

    
      
        ### {{item.product.title}}
        

{{item.variant.price | money}}

        {% assign property_size = item.properties | size %}
        {% if property_size > 0 %}
          {% for p in item.properties %}
            {% assign first_character_in_key = p.first | truncate: 1, '' %}
            {% unless p.last == blank or first_character_in_key == '_' %}
              #### Fundraiser: {{ p.last }}
              {% if p.last contains '/uploads/' %}
                {{ p.last | split: '/' | last }}
              {% else %}

              {% endif %}
              

            {% endunless %}
          {% endfor %}
        {% endif %}
        

          

QTY

          -
          
          +
2

Here is my js for the QTY selector

$(".increase").click(function() {
  $("input").val(function(i, oldval) {
    return ++oldval;
  });
});

$(".decrease").click(function() {
  $("input").val(function(i, oldval) {
    if (oldval > 1) {
      return --oldval;
    } else {
      return oldval;
    }
  });
});