[RESOLVED] Sum function using Combobox data

[mortezataheri]

I have 3 textboxes and 1 combobox.
txtpresence = calculated via other textboxes
txtProduction = enters by user
cboScore = 0 -25 selected by user

txtEfficiency = populated with summation result

Private Sub txtPresence_Change()
 If Me.txtPresence.Value <> vbNullString Then
    If IsNumeric(Me.txtPresence.Value) = True Then
       If Me.txtProduction.Value <> vbNullString Then
          If IsNumeric(Me.txtProduction.Value) = True Then
             If Me.cboScore.Value <> vbNullString Then
                If IsNumeric(Me.cboScore.Value) = True Then
            Me.txtEfficiency.Value = [CDbl(Me.txtProduction.Value) / CDbl(Me.txtPresence.Value) * 75] + CDbl(Me.cboScore.Value)
                End If
             End If
          End If
       End If
    End If
 End If
End Sub

Private Sub txtProduction_Change()
 If Me.txtProduction.Value <> vbNullString Then
    If IsNumeric(Me.txtProduction.Value) = True Then
       If Me.txtPresence.Value <> vbNullString Then
          If IsNumeric(Me.txtPresence.Value) = True Then
             If Me.cboScore.Value <> vbNullString Then
                If IsNumeric(Me.cboScore.Value) = True Then
             
             Me.txtEfficiency.Value = [CDbl(Me.txtProduction.Value) / CDbl(Me.txtPresence.Value) * 75] + CDbl(Me.cboScore.Value)
                End If
             End If
          End If
       End If
    End If
 End If
End Sub

Private Sub cboScore_Change()
 If Me.cboScore.Value <> vbNullString Then
   If IsNumeric(Me.cboScore.Value) = True Then
      If Me.txtPresence.Value <> vbNullString Then
         If IsNumeric(Me.txtPresence.Value) = True Then
            If Me.txtProduction.Value <> vbNullString Then
               If IsNumeric(Me.txtProduction.Value) = True Then
             
             Me.txtEfficiency.Value = [CDbl(Me.txtProduction.Value) / CDbl(Me.txtPresence.Value) * 75] + CDbl(Me.cboScore.Value)
                End If
             End If
          End If
       End If
    End If
 End If
End Sub

It gives error on this line for cboScore declaration

            Me.txtEfficiency.Value = [CDbl(Me.txtProduction.Value) / CDbl(Me.txtPresence.Value) * 75] + CDbl(Me.cboScore.Value)

Should i use another term instead of CDbl(Me.cboScore.value) or there's something else wrong in my code?