Problem statement
We want to request the /delegation endpoint be enabled for our tenant. We ‘accidentally’ deleted our tenant, have no backups, so we created a new tenant and requested that the legacy /delegation endpoint be enabled.
Solution
This endpoint has been disabled by default for tenants since 2017, as described here:
https://auth0.com/docs/api/authentication#delegation
It may be possible to enable this endpoint in very specific circumstances and in order to do so contact our @support group through a private message here in the forum.