Hi @diego.veras,
Welcome to the Auth0 Community!
The client requires organization membership but user does not belong to any organization error happens when the connection the user belongs to is not enabled for the organization. Because of this, the user will not be allowed to authenticate until the connection is enabled for that organization.
This is mentioned in this knowledge solution.
Additionally, you should not be experiencing a redirect loop. If this is happening, I recommend checking your network activity and tracing the events happening there. It may also be worth checking your tenant logs to see what is happening on the server side.
Let me know how this goes for you.
Thanks,
Rueben