Keyclaok and Rocket chat

I have a node js server which uses apis provided by keycloak to authenticate a user.
I need to configure rocket chat so that I dont need to generate rocket chat access token again and use the same token generated by keycloak for my web app;
Note → I have a user A with password B . When I try to click on login using keycloak on rocket chat login dashboard and enter these creds A and B then it allows me to login…when I try to get user list by an api using the token generated by login api of rocket chat it allows to do so…but when I use keycloak token generated by me node server with same creds A and B for same client is shows 401 and message as you must be logged in to do this…How can I use the same keycloak token for rocket chat access as well?