Not getting the "Submit for verification" button for OAuth verification in GCP

Question

I have created a Gmail/Calendar add-on in Google Apps Script and I want to publish it to the marketplace.

I am following the steps at https://developers.google.com/workspace/marketplace/configure-oauth-consent-screen#fill_out_the_oauth_consent_screen. I am on the "Submit for OAuth verification" step which leads to https://support.google.com/cloud/answer/9110914#submit-howto. It says:

4. Click the Edit App button.
5. Enter the information required on the configuration page, and then click Submit for verification. If the submit for verification button does not appear at the end of the configuration pages, save what you have completed and repeat steps 1-4.

I have gone through all the steps but the Submit for verification never comes up. I'm not sure what I am doing wrong?