Error with Okta as Oauth2 Identity Provider (OIDC connection)

Problem statement

I’m trying to log in with Okta OIDC from Universal Login (Auth0 as SP) with the Okta connection button, but it comes back with an error.

Error in the test page:
"the resource owner or authorization server denied the request"

Callback with error: “Status 400”

Steps to reproduce

Follow the 6 steps here, and then either of the below steps:

  1. Try the connection button within the dashboard
  2. Login and click on the connection button


As explained in this article,

Using the URL of the form requires an additional 
paid feature of API Access Management which is used for custom authorization servers.


As per this article,

Instead, use the URL` to access the default authorization server for Okta without API Access Management.`

The changes should be done within the connection in both:

  1. Authorization URL
  2. The request in the Fetch User Profile Script