WC_qty, Custom quantity field

Hello! If you use WC_qty for the quantity of a product, then when the quantity of an item increases on the product page, the price is not recalculated, and if you use a custom field for the quantity of an item, then its change leads to a recalculation of the price, but in this case there is no way to add the same item to the cart other characteristics, because a message appears stating that it is not possible to add this product to the cart again, although it has different characteristics. How can this be done so that a change in the quantity of an item leads to a dynamic recalculation of the cost and at the same time, it is possible to add the same item to the cart, but with different characteristics?