Camunda 8 Webmodeler identity/user details Fetch 400 Error

Hi Team,
I am using Self Managed and deployed in to Openshift Successfully.
All the components are running successful. My Keycloak is connecting with OIDC for the authentication and authorization.
When I try to add collaborator from the web modeler project, when I search the users, It says https:webmodeler/identity/users?search=vinoth … response is 400 bad request. Any idea why this error occurs .
But users are properly listed in the identity under users tab.

Did you check web modeler roles for this user?