firestore does not exist

[martinmoose]

In the following code it says that firestore does not exist for firebase?

From board.service.ts

  /**
   * Remove a specifc task from the board
   */
  removeTask(boardId: string, task: Task) {
    return this.db
      .collection('boards')
      .doc(boardId)
      .update({
        tasks: firebase.firestore.FieldValue.arrayRemove(task)
      });
  }