public Response <string> RegisterDiscount(string orderId, IDiscountService discountService) { try { var order = FindOrderById(orderId); } catch (Exception) { return(Response <string> .Error($"Order with id: {orderId} not found!")); } try { var discountServiceId = orderRepository.AddDiscountToOrder(orderId, discountService); return(Response <string> .Success($"Discount with id: {discountServiceId} added to order.")); } catch (Exception ex) { return(Response <string> .Error(ex.Message)); } }