Keycloak needs to authenticate users with no role

Hi,
I’m working on saml based authentication. The requirement is that login to app roles are not needed.

In the web.xml file

<security-constraint>
    <web-resource-collection>
        <web-resource-name>applicant-login-required</web-resource-name>
        <url-pattern>/login/*</url-pattern>
       <http-method-omission>OPTIONS</http-method-omission>
    </web-resource-collection>
    <auth-constraint>
        <role-name>Admin</role-name>
    </auth-constraint>
</security-constraint>

The application not dependent on the user role. so we try to remove the auth constraint and the security role but it won’t work. Once we removed it is directing to / login endpoint. but before it is redirecting to https://localhost:8543/auth/realms/comic-auth/protocol/saml. /login endpoint is the service provider consumerurl. is there are any way authenticate a user without any roles?