Failure in starting business processes or aborting tasks after implementing LDAP integration in Process Automation Manager

Issue

• After implementing LDAP integration in Process Automation Manager (RHPAM) to authenticate against Active Directory service, we are unable to start jBPM business processes as before with errors like below:

01:03:57,895 ERROR [org.jbpm.services.task.wih.LocalHTWorkItemHandler] (default task-13) Sat May 23 01:03:57 JST 2020: Error when creating task on task server for work item id 1. Error reported by task server: There are no known Business Administrators, task cannot be created according to WS-HT specification: org.jbpm.services.task.exception.CannotAddTaskException: There are no known Business Administrators, task cannot be created according to WS-HT specification
    at org.jbpm.services.task.commands.UserGroupCallbackTaskCommand.doCallbackOperationForPeopleAssignments(UserGroupCallbackTaskCommand.java:279)
    at org.jbpm.services.task.commands.AddTaskCommand.execute(AddTaskCommand.java:112)
    at org.jbpm.services.task.commands.AddTaskCommand.execute(AddTaskCommand.java:56)
......

• When trying to implement LogCleanupCommand in a RHPAM instance that integrated with AD via LdapExtLoginModule, getting warning message like below and unable to call LogCleanupCommand successfully.

2020-05-21 15:19:02,950 WARN  [org.jbpm.services.task.persistence.TaskTransactionInterceptor] (default task-1) Could not commit session: java.lang.IllegalArgumentException: User Administrator was not found in callback org.jbpm.services.task.identity.LDAPUserGroupCallbackImpl@405babf6
        at org.jbpm.services.task.commands.UserGroupCallbackTaskCommand.doCallbackUserOperation(UserGroupCallbackTaskCommand.java:108)
        at org.jbpm.services.task.commands.ExitTaskCommand.execute(ExitTaskCommand.java:48)
......