I'm working with AWS API Gateway and I'm getting the following error:

Uncaught TypeError TypeError: Failed to fetch

My API is just returning a simple JSON string. I can get a successful response with curl, Postman and testing via the AWS console. But, using JavaScript, I get an error. I suspect that AWS requires a specific header

I separated the code from the original website. Some unnecessary parts have been removed.

<script type = "text/javascript">
const GET_url = '<url>'
const POST_url = '<url>'

async function getInvokeFromAPI() {
  const response = await fetch(GET_url, {
    method: 'GET'
  });
  const data = await response.json();
}

async function postInvokeFromAPI() {
  const respone = await fetch(POST_url, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
    }
  });
  const data = await response.json();
}
</script>