How to get a JWT token when not logged in

Question

If I am logged in (have a session cookie) and make a GET request to /jwt/token, then I get a JWT token. How do I get the token if I am not logged in?

This article by Preston So states:

As a logged-in user, or when you issue a GET request against /jwt/token with credentials of a user with the appropriate permissions, you will receive a token like that seen below, with which we can issue authenticated requests to Drupal.

So this is what I tried in Postman:

• GET: example.com/jwt/token
• Headers: Content-Type: application/json
• Body: raw: {"name": "myUsername", "pass: "password"}

This resulted in an "access denied" message.

I also tried using form-data and x-www-form-urlencoded for the Body, but those didn't work either.

I know JWT is configured correctly because if I log in first in Postman (get a session cookie) and then try the request, it gives me the token.

So what can I use in Postman to get the token from /jwt/token when I'm not already logged in? (How do I provide my login info to Postman?)