Hi @Rub32,
Welcome to the Community.
What are you trying to do with the management API? Auth0 automatically limits what scopes a SPA can request from the management API. The node-auth0 library is not intended for use in a single page app, and this could explain some of the complications you are running into.
If you want to build out a way for users to manage their own profiles, we recommend doing so through a proxy API. Here is an example of how to set up a flow for a user to change their email: