[Knob addon] do not work and dissapear when selecting other component

Describe the bug I want to use knob on a component. I see the knob when I ferst open the storybook.

1. My first issue is that I change the storybook field, and I do not see the change reflected on the component
2. When I go to other version of my component, and go back again to the component where I have the knob enabled, it is not there anymore.

To Reproduce This is the code of my story

import React from "react";
import { withKnobs, text } from "@storybook/addon-knobs";

import CardItem from "./CardItem";

export default {
  component: CardItem,
  title: "app/components/CardItem/CardItem"
};

const cardItem = {
  imageurl: "https://media1.giphy.com/media/26tPtg8M3i6DPSSt2/200w.gif",
  imagealt: "react-gif",
  title: text("Title", "Title number 1"),
  body: "This is the body",
  firstButtonText: "See",
  secondButtonText: "Help"
};
const props_no_body = { ...cardItem, body: null };
const props_no_second_button_text = { ...cardItem, secondButtonText: null };

export const Full = () => <CardItem {...cardItem} />;
Full.story = {
  name: "Full Card, all props",
  decorators: [withKnobs]
};

export const no_body_text = () => <CardItem {...props_no_body} />;

export const no_second_button_text = () => (
  <CardItem {...props_no_second_button_text} />
);

My configurations

$ cat .storybook/addons.js 
import '@storybook/addon-actions/register';
import '@storybook/addon-links/register';
import '@storybook/addon-knobs/register';

$ cat .storybook/config.js 
import { configure } from '@storybook/react';
configure(require.context('../src', true, /\.stories\.js$/), module);

$ cat package.json |grep storybook
    "@storybook/addon-knobs": "^5.2.8",
    "@storybook/addon-actions": "^5.2.8",
    "@storybook/addon-links": "^5.2.8",
    "@storybook/addon-storyshots": "^5.2.8",
    "@storybook/addons": "^5.2.8",
    "@storybook/react": "^5.2.8",
    "storybook-cartesian": "^2.1.1",
    "storybook": "start-storybook -p 9009 -s public",
    "build-storybook": "build-storybook -s public"

[gonzaloamadio]

@shilman I have sent you an invitation to my repo called “fuse-react”. Here is the link just in case: https://github.com/gonzaloamadio/fuse-react/invitations. Check the branch called ‘gonza-dev’

[gonzaloamadio]

Yes @shilman , it is working. I leave my working example just in case. Thank you!

import React from "react";
import { withKnobs, text } from "@storybook/addon-knobs";
import CardItem from "./CardItem";

export default {
  component: CardItem,
  title: "app/components/CardItem/CardItem"
};

const cardItem = () => ({
  imageurl: "https://media1.giphy.com/media/26tPtg8M3i6DPSSt2/200w.gif",
  imagealt: "react-gif",
  title: text("Title", "Elongacion de columna"),
  body: "Este es un ejercicio que sirve para estirar los lumbares.",
  firstButtonText: "Ver",
  secondButtonText: "Ayuda"
});

const props_no_body = { ...cardItem(), body: null };

export const Full = () => <CardItem {...cardItem()} />;
Full.story = {
  name: "Full Card, all props",
  decorators: [withKnobs]
};

export const no_body_text = () => <CardItem {...props_no_body} />;