The 'role' field is missing in SAML response

While accessing splunk through Onelogin, i am getting a error message on the splunk login page as "The 'role' field is missing in the saml response from the IdP. Fix the configuration in the IdP to include 'role' in the saml response to complete login successfully. Click here to return to Splunk." How do i fix this with splunk SAML configuration. -Thanks