As per the exchange prescribed guidelines on the Two Factor Authentication for the trading platforms, we're in the progress of going live with the new login Single Sign On (SSO) module and changing our login flow to support 2FA across all the FYERS platforms.  

To Make the transition seamless for all API users, we have released a sandbox environment to test the new login flow with their respective applications, as existing production API services will switch to the new flow by September 30. 

For the sandbox environment link, click here.

For more information, refer to this document.