JIRA OAuth 2 redirects to the app's callback URL without authorization code

[Tuan Nguyen]

I am having an issue when trying to integrate my app with JIRA using the 3LO OAuth2 flow.

I follow the article below: 

https://developer.atlassian.com/cloud/jira/platform/oauth-2-authorization-code-grants-3lo-for-apps/

At step 1. Direct the user to the authorization URL to get an authorization code, I can't receive an authorization code after accepting the access. The JIRA OAuth 2 redirect to my callback URL without a query parameter called code (just my callback URL and don't have any query parameters)

What am I doing wrong?

Thanks & Best Regards

Tuan