In the next lecture, we will be adding a number of configuration properties to the Mailer. Due to a major Sendgrid update, we will no longer be able to use no-reply@emaily.com

When we write out this line:

this.from_email = new helper.Email('no-reply@emaily.com');

We instead need to use the email address of the "Sender" that we configured in the new setup notes:

https://www.udemy.com/course/node-with-react-fullstack-web-development/learn/lecture/19299818#questions

You will not be able to use the API if you have not created and verified the Sender and generated an API key for that Sender.