Excel item scan out with barcode scanner with text strings varies

If my length of character of text box value vary, from product to product then below is not working.File is attached.

[VBA]
If Len(Me.TB1.Value) <> 12 Then Exit Sub
[VBA]

please help me

[VBA]
rivate Sub TB1_Change()
Dim rng As Range
If Len(Me.TB1.Value) <> 12 Then Exit Sub
With ThisWorkbook.Sheets("Stock")
Set rng = .Range("A:A").Find(Me.TB1.Value, , xlValues, xlWhole)

If Not rng Is Nothing Then
Me.PN.Caption = rng.Offset(0, 1)
Me.LOC.Caption = rng.Offset(0, 3)
Me.QTY.Caption = rng.Offset(0, 2)
Else
MsgBox "Part Number Not Available "
End If
End With

Me.TB1.SelStart = 0
Me.TB1.SelLength = Len(Me.TB1.Value)

End Sub
[VBA]

Below code works for copy & paste. but barcode scanner not working. Barcode scanner displays only first strings

{VB}
Private Sub TB1_Change()
Dim LT As Integer
LT = Len(Me.TB1.Value)
Dim rng As Range
If Len(Me.TB1.Value) <> LT Then Exit Sub
....

.
.
.

{VBA}

please help for barcode scanner

Thanks a lot. it works fine

if possible please help for message box data
msg box is not popup when part number is not in list