What was wrong?

Question

JavaScript

Tried to connect to wordpress using react and get data from it, but got TypeError: "this.state.title is undefined".
Consider adding an error boundary to your tree to customize error handling behavior.
Visit https://fb.me/react-error-boundaries to learn more about error boundaries.

What are they connected with?

import React from 'react';
import './App.css';

class App extends React.Component {
  constructor(props) {
    super(props)

    this.state = {
      title: {},
      date: "",
      content: {}
    };
  }


  componentDidMount() {
    return fetch(`http://mysite.loc/wp-json/wp/v2/posts/`)
      .then((response) => response.json())
      .then((responseJson) => {
        const { title, date, content } = responseJson;
        this.setState({ title, date, content });
      })
      .catch((error) => {
        console.error(error);
      });
  }

  render() {
    return (
      <div>
        <div>
          <div className="row">
            <div className="leftcolumn">
              <div className="card">
                <div className="title">
                  <h1>{this.state.title.rendered}</h1>
                  <p> {this.state.date} </p>
                </div>

                <div
                  className="content"
                  dangerouslySetInnerHTML={{ __html: this.state.content.rendered }} />
              </div>
            </div>
          </div>
        </div>
      </div>
    );
  }
}


export default App;