Hi Bob
Well Gasman gave you the solution as to how you can achieve this.
All I am trying to do is point out that the structure of the Subform is wrong.
So the Subform for entering Invoice Number information must be based on a query based on Multiple Tables.
The Subform has Multiple Redundant Controls because all you actually need to enter in the Subform is the "Date", "Invoice Number" & "Amount"
OK
Don't know if the following would help, would changing this line of Code:-
If Me.cboCustomerStatusID = 1 Then 'Normal Status
to
If Me.cboCustomerStatusID.Column(0) = 1 Then 'Normal Status