Adds a DiscountCode to the Cart to activate the related Cart Discounts.
Adding a Discount Code is only possible if no DirectDiscount has been applied to the Order.
The maximum number of Discount Codes in a Cart is restricted by a [limit](/../api/limits#carts).
Specific Error Code: [MatchingPriceNotFound](ctp:api:type:MatchingPriceNotFoundError)
Adds a DiscountCode to the Cart to activate the related Cart Discounts. Adding a Discount Code is only possible if no DirectDiscount has been applied to the Order.