Oauth error invalid_request: The redirect_uri is not whitelisted

Oauth error invalid_request: The redirect_uri is not whitelisted

Im creating app from doc - get the error the app works with ngrok but the error appears while pushing to heroku

Oauth is connected here is the video → https://www.youtube.com/watch?v=F_0tUl7P_DA

Here is the solution
HOST={your app’s host} # Your app’s host, without the protocol prefix