ERR_NGROK_3115: The redirect_uri configured for this application is not properly configured or whitelisted with PROVIDER - ngrok documentation

What does ERR_NGROK_3115 mean?

ngrok returns ERR_NGROK_3115 with this message:

The redirect_uri configured for this application is not properly configured or whitelisted with <PROVIDER>.

Contact the owner of this application in order to fix this error.

Where can I get more help with ERR_NGROK_3115?

Email support@ngrok.com and include the error code.