golang从指针类型切片复制指针值

type Order struct {
    *Res
    Status int
}

type Res struct {
    ResID            int64
    OtaBookID        string
    StayDetail       []*ResElement
    TotalCharge      float64
    CustFName        string
    CustLName        string
    CreateTime       time.Time
}

type ResElement struct {
    Res        *Res
    OtaEleID   string
    OtaRoomID  string
    RoomID     int
    Arrival    time.Time
    Depart     time.Time
    Charge     float64
    CreateTime time.Time
}

I have a slice named orderList to record orders. Now i have the first order which OtaBookID is "A123", and i want to copy this order and change its OtaBookID to "B123". The ResElement type have some other detail info to record this order and i hide them because it not affect my question. I can success change Res.OtaBookID but i have no idea how to change Res.StayDetail[0].Res.OtaBookID

func main() {
    var orderList []*Order

    res := new(Res)
    res.OtaBookID = "A123"

    resElt := new(ResElement)
    resElt.Res = res
    res.StayDetail = append(res.StayDetail, resElt)

    order := new(Order)
    order.Res = res

    orderList = append(orderList, order)

    originalOrder := new(Order)
    originalOrder.Res = new(Res)
    *originalOrder.Res = *order.Res
    //originalOrder.Res.StayDetail[0].Res.OtaBookID = "B123" //this will make all become "B123"

    originalOrder.Res.OtaBookID = "B123"

    orderList = append(orderList, originalOrder)

    fmt.Println(orderList[0].Res.OtaBookID)  //A123
    fmt.Println(orderList[1].Res.OtaBookID)  //B123
    fmt.Println(orderList[0].Res.StayDetail[0].Res.OtaBookID)  //A123
    fmt.Println(orderList[1].Res.StayDetail[0].Res.OtaBookID)  //A123, i want this become B123
}

The result i want is orderList[0].Res.OtaBookID and orderList[0].Res.StayDetail[0].Res.OtaBookID is "A123" and other is "B123"

ps: Because i'm taking over other's works. So the three type already fixed and can not adjust. I want to know in this situation whether have any method to arrive my goal