Attachment in an edit mode document

Hi,

i would like to know how i should do the script when i wanted the user to attach a doclink in a specific field when DueDate is less than 3 days of DateComposed. I have the script below but the problem is after the error message prompted, when the user attach the doclink, the error message prompt again. i don’t know if i should use a looping here…here’s my script:

Sub Querysave(Source As Notesuidocument, Continue As Variant)

Dim todayDateTime As NotesDateTime

Dim dueDateTime As NotesDateTime

Dim daysLeft As Long

Call source.Refresh

Set todayDateTime = New NotesDateTime( source.FieldGetText("DateComposed") )    

Set dueDateTime = New NotesDateTime ( source.FieldGetText( "DueDate" ) )

daysLeft = ( dueDateTime.TimeDifference ( todayDateTime ) ) / 86400



If daysleft < 3 Then

	If source.document.HasItem("Reason") Then 

		Set varBody = source.document.GetFirstItem("Reason") 

		If source.document.HasItem("$Links") Then

			Set varLinks = source.document.GetFirstItem("$Links") 

		Else

			Messagebox "Please attach a link in the Reason field"

			continue = False

		End If

	End If

End If

Exit Sub

End Sub