Why am I getting an empty body response for user feedback in sentry?

I am using ReactJS to set up the user feedback for Sentry.

I initialize it with:

import Raven from 'raven-js';

Raven.config(https://#########@sentry.io/#######, {
  environment: "development",
}).install();

And used the componentDidCatch in ErrorBoundary(https://reactjs.org/docs/error-boundaries.html) concept to show the report dialog.

componentDidCatch(error, info) {
    this.setState({ hasError: true });
    Raven.captureException(error, { extra: info });
    Raven.showReportDialog();
}

When I submit the dialog, the network shows me a POST request with a 200 Response and a confirmation dialog that it was successful. However, the body is empty and the submitted form can’t be seen in the user feedback section of my project on my sentry account.

The behavior looks as seen on this site: https://wiggly-power.glitch.me/