Keycloak new admin user : access forbidden

Hi All,
Very new to keycloak world. I recently deployed a keycloak server (version 18.0.0) using ansible. I created a initial admin account. Everything is working as expected. But when i tried to create a new admin account on master realm and trying to give it admin role, i get forbidden (You don’t have access to the requested resource.) Is there a reason for this?
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