Count distinct values that correspond to a criteria

Hi,

I have a list of Customer and Items they have ordered.

I have this code that counts how many orders have been placed for 2 specific items (TBA and 8IM) and places the value in worksheet List cell A1:

Sub CountItems()
Dim wsd As Worksheet, wsc As Worksheet
Dim Lastrow As Long, i As Long, J As Long
Dim Cell As Range

Set wsc = Sheets("List")
Set wsd = Sheets("Jan")

i = 0

Application.ScreenUpdating = False

With wsd
    Lastrow = .Range("B" & Rows.Count).End(xlUp).Row
    For Each Cell In .Range("B2:B" & Lastrow)
        If Cell = "TBA" Or Cell = "8IM" Then
i = i + 1
        End If
    Next Cell
End With
 
With wsc
    .Range("A1").Value = i

End With

Application.ScreenUpdating = True

End Sub

I would need some suggestions how to amend this code to count how many Customers have ordered either item TBA or item 8IM. If a Customer ordered at least once any of these items it has to be counted as 1.

Thanks,
Eduard