Zerodha Kite Access Token Issue Resolution

I'm facing an issue in the development environment with Zerodha Kite. The system is unable to generate the access token for an API key user, returning the message "The user is not enabled for the app."

Key Requirements:
- Expertise in troubleshooting Zerodha Kite API issues
- Strong understanding of access token generation process
- Experience with development environment configurations
- Ability to resolve issues related to API key users

Please note, the app is already registered with Zerodha Kite's API. Immediate assistance would be appreciated.