Admin API execution when authentication type is strategy


I am using keycloak for Node-RED authentication.
Since I am using admin auth type strategy admin api /auth/token gives 404 cannot post error
If I use admin auth type password then everything works fine.

I want to execute admin API outside the Node-RED editor. How to execute them when we use strategy in admin auth?

In docs i see grant-type must be password for admin /auth/token API.