[keycloak-user] programatically create user gives 400 bad request

Hi, I have a standard keycloak 1.7.0-Final and a separate jax-rs service (both in docker) to create a simple test-user programatically with hardcoded params: @Path("users") @Stateless public class UsersResource { @POST public Response createTestUser() { Keycloak kc = Keycloak.getInstance( "http://192.168.99.100:8180/auth", "master", "admin", "password", "security-admin-console"); CredentialRepresentation credential = new CredentialRepresentation(); credential.setType(CredentialRepresentation.PASSWORD); credential.setValue("test123"); credential.setTemporary(false); / UserRepresentation user = new UserRepresentation(); user.setUsername("testuser"); user.setFirstName("Test"); user.setLastName("User"); user.setCredentials(Arrays.asList(credential)); user.setEnabled(true); user.setRealmRoles(Arrays.asList("admin")); Response result = kc.realm("master").users().create(user); return result; } } But calling the JAX-RS endpoint returns in a delegated 400 Bad request. The KC log states only: 00:40:23,436 WARN [org.keycloak.events] (default task-9) type=LOGIN_ERROR, realmId=master, clientId=security-admin-console, userId=null, ipAddress=172.17.0.1, error=not_allowed, grant_type=password, auth_method=oauth_credentials, client_auth_method=client-secret Any ideas? Kind regards, Dirk