html - Add to Cart button missing ID -

my add cart button on shopify front page not getting added cart. gives error when clicking:parameter missing or invalid: required parameter missing or invalid: id

the form looks this:

                <form action="/cart" method="post" enctype="multipart/form-data" id="addtocartform" value="{{ item.variant.id }}">                <span id="productprice" class="h1 price" itemprop="price">                 {{ current_variant.price | money }}               </span>                {% if product.compare_at_price_max > product.price %}                 <p id="compareprice" class="h3 price">                   {{ current_variant.compare_at_price | money }}                 </p>               {% endif %}                <div class="form__row" style="margin-top: 10px">                    <select name="id" id="productselect" class="product-single__variants">                     {% variant in product.variants %}                       {% if variant. available %}                          <option {% if variant.id == current_variant %} selected="selected" {% endif %} data-sku="{{ variant.sku }}" value="{{ variant.id }}">{{ variant.title }} - {{ variant.price | money_with_currency }}</option>                        {% else %}                         <option disabled="disabled">                           {{ variant.title }} - {{ 'products.product.sold_out' | t }}                         </option>                       {% endif %}                     {% endfor %}                   </select>  <div class="form__column quantity-selector">                     <label for="antal" class="quantity-selector">{{ 'products.product.quantity' | t }}</label>                     <input type="number" id="antal" name="antal" value="1" min="1" class="qty-remove-defaults quantity-selector">                   </div>                    <div class="form__column">                     <button href="/cart" type="send" name="tilføj" id="addtocart" class="btn btn--fill btn--regular btn--color">                       <span id="addtocarttext">{{ 'products.product.add_to_cart' | t }}</span>                     </button>                   </div>                 </div>              </form> 

is because it's missing variant.id paraemeter? liquid knowledge little.