If you find that a user is unable to login with an external login provider getting stuck in the Register page, it's probably due to that there's an old or incorrect SysUser or SysExternalLogin objects in the database.

Do this;

1. Please note that if you application is running, the user should log out and close their browsers.
2. Remove all previous SysUser and SysExternalLogin objects, preferrable from inside your application to make the syncing of objects remove them from server memory. If you need to do it from the database directly, restart the Turnkey server or wait at least 15 minutes for the objects to be removed from running EcoSpaces.
3. If the external login is with Google (for example), also ask the user to go to Google account view and remove the application approval for your application.

After these steps, the correct SysUser and SysExternalLogin objects should be recreated the next time the user authenticates with the social login service.