I have a `en.json` file as below:

```js
{
    "doorClosing": {
      "defaultMessage": "Doors closing",
      "description": "Elevator doors are being closed"
    },
    "floorSelected": {
      "defaultMessage": "Floor selected: {floorSelected}",
      "description": "`The floor ${lift.floorSelected} has been selected`"
    },
    "floorSelectedInvalid": {
      "defaultMessage": "Invalid floor",
      "description": "The selected floor is not valid"
    },
    "idle": {
      "defaultMessage": "",
      "description": ""
    },
    "init": {
      "defaultMessage": "Initialisation",
      "description": "The system is being initialized"
    },
    "liftMoving": {
      "defaultMessage": "Elevator moving",
      "description": "Elevator is being moved to the floor selected"
    }
}

```

Then later in the code, I use `let dashboardMsg = intl.formatMessage({id:msg});` where msg is one of the key contained in the json file.  

About the key `floorSelected`, when I use it `${lift.floorSelected}` is not translated by the number contained in this variable.  

What's wrong? Is there another way or do I have to do that manually?