trigger <str> cannot delete record being modified or stored

  Explanation:  The trigger specified (possibly invoked by another
  trigger)  attempted  to delete a record that was currently being
  stored or modified (by  either  a  user  request  or  a  trigger
  action).

  User Action:  First, review  the  database  design  and  defined
  triggers.   Then,  define  one  or more of the triggers again to
  eliminate the possibility of deleting a  record  that  is  being
  modified or stored.