سلام میخوام یه رکورد به جدول order اضافه کنم اما این خطا رو میده

Cannot insert explicit value for identity column in table 'Orders' when IDENTITY_INSERT is set to OFF.

کلاس order

public partial class Order
    {
        public Order()
        {
            OrderAdditionalItems = new HashSet<OrderAdditionalItem>();
            OrderItems = new HashSet<OrderItem>();
            OrderPayments = new HashSet<OrderPayment>();
        }
        
        public int ID { get; set; }

        public DateTime ODate { get; set; }

        public int UserID { get; set; }

        public int TransferID { get; set; }

        public decimal TransferCost { get; set; }

        public int AddressID { get; set; }

        public int Status { get; set; }

        [StringLength(50)]
        public string TransferCode { get; set; }

        public string CustomData { get; set; }

        public virtual ICollection<OrderAdditionalItem> OrderAdditionalItems { get; set; }

        public virtual ICollection<OrderItem> OrderItems { get; set; }

        public virtual ICollection<OrderPayment> OrderPayments { get; set; }

        public virtual TransferType TransferType { get; set; }

        public virtual UserProfile UserProfile { get; set; }
    }

کد اضافه کردن

 Order openorder = new Order();
                    openorder.Status = (int)OrderStatus.Open;
                    openorder.UserID = userid;
                    openorder.ODate = DateTime.Now;
                    openorder.TransferID = db.TransferTypes.FirstOrDefault().ID;
                    openorder.AddressID = db.UserAddresses.FirstOrDefault().ID;
                    db.Orders.Add(openorder);
                    db.SaveChanges();

dbcontex

 modelBuilder.Entity<Order>()
                .Property(e => e.TransferCost)
                .HasPrecision(18, 4);

            modelBuilder.Entity<Order>()
                .HasMany(e => e.OrderAdditionalItems)
                .WithRequired(e => e.Order)
                .WillCascadeOnDelete(false);

            modelBuilder.Entity<Order>()
                .HasMany(e => e.OrderItems)
                .WithRequired(e => e.Order)
                .WillCascadeOnDelete(false);

            modelBuilder.Entity<Order>()
                .HasMany(e => e.OrderPayments)
                .WithRequired(e => e.Order)
                .WillCascadeOnDelete(false);

جدول