Code not running properly! Getting error message

I am trying to make a multi value picklist so when a user selects more than one option from the drop down menu, the results show in one cell separated by commas. I found this code online and plugged it into VB on my spreadsheet and it's not working. I'm not a coding expert so I don't know what the solution is. See code below:

Sub DataMultiSelect()
Private Sub Worksheet_Change(ByVal Target As Range)
Dim rngDV As Range
Dim oldVal As String
Dim newVal As String
If Target.Count > 1 Then GoTo exitHandler

On Error Resume Next
Set rngDV = Cells.SpecialCells(xlCellTypeAllValidation)
On Error GoTo exitHandler

If rngDV Is Nothing Then GoTo exitHandler

If Intersect(Target, rngDV) Is Nothing Then
   'do nothing
Else
  Application.EnableEvents = False
  newVal = Target.Value
  Application.Undo
  oldVal = Target.Value
  Target.Value = newVal
  If Target.Column = 12 Then
    If oldVal = "" Then
      'do nothing
      Else
      If newVal = "" Then
      'do nothing
      Else
      Target.Value = oldVal _
        & ", " & newVal
      End If
    End If
  End If
End If

exitHandler:
  Application.EnableEvents = True
End Sub

End Sub

Remove this line from your code -

Sub DataMultiSelect()

. This is line 1 and remove the End Sub at the end. You need to have only 1 End Sub.

Once you remove the top line, what you get is a worksheet event macro. Hence you need to select on your sheet containing the data, right click and select "View Code" and then copy the code in there. As soon as you change the dropdown values, the macro will start working as desired.

Based on your last post in this thread, its apparent that you are satisfied with the solution(s) you've received and have solved your question, but you haven't marked your thread as "SOLVED". I will do it for you this time.

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