Although ____Default Application and ____Default Architecture are in Nolio database, they are hidden.
Root cause is not determined so far. This situation was caused by incorrect records in database.
Took system backup.
Deleted some records from server_flow, published_process, process_container, model_steps and executable table manually, and then the action pack could be deleted.
Not recommend to delete any records by yourself, so please contact CA Support if you face similar issue.