Is there a way to keep Auth0 from creating a new account when someone is logging in via oAuth?

Our experience using Auth0, when a user is authenticating (logging in) using oAuth, and they haven’t used that method before, a new account is created for that user without informing that user this is happening. This causes users with multiple unconnected logins and often then separate profiles in our system. The continuous clean up of this is a giant time-suck.

Is there any way to stop or pause the process to notify the user that the account doesn’t exist and ask if they wish to continue to create a new account? This one step could save many headaches for users and administrators alike.

People have many oAuth accounts and they often don’t share email addresses, or are twitter which doesn’t provide an email address with jumping through hoops. I fully understand a user who may not come to our site that often may not remember how the authenticated with us, try one, apparently succeed, and continue on. We do check email addresses to see if there is an account by this person already, though this doesn’t help in any case where emails don’t match.

Any suggestions on how to solve this will be greatly appreciated.

Thank you,