Private Sub btnSubmit_Click()

Dim ssheet As Worksheet

Set ssheet = ThisWorkbook.Sheets("testing")

nr = ssheet.Cells(Rown.Count, 1).End(xlUp).Row + 1


ssheet.Cells(nr, 1) = CDate(Me.tbDate)
ssheet.Cells(nr, 2) = Me.cmbCartridges
ssheet.Cells(nr, 3) = Me.tbQuantity
ssheet.Cells(nr, 4) = Me.tbEuros


End Sub

Private Sub UserForm_Initialize()
Me.tbDate = Date

'fill combobox
For Each cell In [CartList]
    Me.cmbCartridges.AddItem cell
Next cell

End Sub

nr = ssheet.Cells(Rown.Count, 1).End(xlUp).Row + 1