Hide / Unhide entire rows based on check box selection

I would like to hide specific rows based on whether a check box is ticked.

I have this code but it does not seem to work.

I right clicked on the check box, and assigned this macro:

Private Sub CheckBox68_Click()
    If CheckBox68 = True Then
        [24:26].EntireRow.Hidden = False
    End If
End Sub

I am not sure why it does not work. Can anyone see something wrong with it?

Many thanks in advance Ab