Uncaught TypeError: Cannot read properties of undefined (reading ‘rendered’)

im newbie in React and trying to make a headless worpdpress aplication.
when i fetch a post i get only the first value.

I fetch the post and save it in the state

componentDidMount() {
this.setState({ loading: true }, () => {
  axios.get('http://localhost/wpprojekte/ebike/wp-json/wp/v2/posts/426')
    .then(res => {
      this.setState({ loading: false, error: 'no error', post: res.data })
    }).catch(error => {
      console.log(error);
    });
});}

I have now the post in my state which looks like

constructor(props) {
super(props);
this.state = {
  loading: false,
  error: 'error',
  post: {},
}}

when i render the Component, i can get only the first value from the post.
for example this.state.post.date

when i try to get this.state.post.title.rendered

Uncaught TypeError: Cannot read properties of undefined (reading 'rendered')

here is The render function

render() {
return (
  <div>
    {<div dangerouslySetInnerHTML={{ __html: this.state.post.title.rendered }} />}
  </div>
)}

I dont understand why it is getting only the first value.