Update: The information below although not very old is already outdated because Google changed the way they convene information from the application that is asking for user authentication. It now seems to be based on the configured redirect URL (hostname) so the configured application name/logo may not have an impact.
The behavior you described will happen if you enabled the Google social connection and did not configure your own client information. By default the connection will use Auth0 developer keys for testing purposes and this will mean the information that will be shown will be Auth0 related.
When using the Auth0 developer keys, the consent screen for the various Identity Providers will display Auth0’s logo and information to your users.
You can follow the instruction at the following link to configure your own set of keys: