This is how Discord themselves advise the flow to work:
promptcontrols how the authorization flow handles existing authorizations. If a user has previously authorized your application with the requested scopes and prompt is set toconsent, it will request them to reapprove their authorization. If set tonone, it will skip the authorization screen and redirect them back to your redirect URI without requesting their authorization. For passthrough scopes, likebotandwebhook.incoming, authorization is always required.
emphasis:
If set to
none, it will skip the authorization screen
Not showing the authorization screen at all is something that only Discord themselves can control; this is not on us to fix (with prompt=none set).