Goto layout name by calculation
I list useful layout names for users to select and open it. Layout will be displayed by "Goto Layout [$Layoutname]" which is done by "layout name by calculation". It works for most of layout, except few layouts. For example, I have one layout, name by "customer". It cannot be shown. I search all layouts and there is one "customer" layout only. It works, if I rename the layout to "customer1". Why it cannot be named by "customer" and open by "Goto Layout [$Layoutname]"?