When I logged in as the non-admin user and trying to search an user I am getting below error. While the admin is able to search users with no error. Any help would be appreciated.

Error for non admin users

2017-10-06 08:03:53,415 [DEBUG] VirtualDataModel [RBPM] VDM.getEntityDefinition(String, Locale):user
2017-10-06 08:03:53,415 [DEBUG] VirtualDataAccess [RBPM] VDA.getEntityResultList query filter: (&(objectClass=inetOrgPerson))
2017-10-06 08:03:53,415 [DEBUG] VirtualDataAccess [RBPM] Query Filter type= 2, LDAP attr=null, relOp=null, val=(|(mail=**zzz**)(givenName=**zzz**)(sn=**zzz** ))
2017-10-06 08:03:53,415 [ERROR] TargetSetService [RBPM] Unknown service failure.