Issues with Creating Bot User Log-In

I’ve been trying to add a log-in feature for my bot users. Once users log in, I need to route returning users differently based on past inputs.

I’m using OAuth v2 with Google but have ended up with errors. When I test the Authorization Profile under Configurations, it says the test is successful, But, I have problems when adding a Custom Authentication service to a dialog task. The Google sign-in page sometime redirects to a blank page with a URL starting with “…” but no actual successful response from the chatbot. Other times it shows an error “BadRequest-Cannot read property ‘idp’ of undefined” but I’ve checked and the callback URL is correct.

Is there a better way to accomplish this without integrating OAuth v2? If not, how can I troubleshoot?