Have a need to get the value of the parent document's field name BeneficiaryName for the child doc.  Here is my code...

Sub Postopen(Source As Notesuidocument)
    Dim session As New NotesSession
    Dim db As NotesDatabase
    Dim doc As NotesDocument
    Dim ParentDoc As NotesDocument
    Dim parentUnid As String
    
    Set db = session.CurrentDatabase
    Set doc=source.Document    
    
    parentUnid = doc.ParentDocumentUNID

===>>>    Set ParentDoc = db.GetDocumentByUNID( ParentUnid )

    doc.BeneficiaryName = ParentDoc.BeneficiaryName(0)
    Call doc.Save(True, False)
    Call source.Refresh
    
End Sub

It errors out when I try to use ParentUnid to get the value for the child doc.

Does anyone see what I'm doing wrong?

Help appreciated!

Marcus