Command dosen't work in mac App

hallo,

if not Identificativo then
let y := year('ID NOTA'.DATA.DATA);
let m := month('ID NOTA'.DATA.DATA);
let d := day('ID NOTA'.DATA.DATA);
let c := cnt(select 'ID Nota' where year('ID NOTA'.DATA.DATA) = y and month('ID NOTA'.DATA.DATA) = m);
Identificativo := y + format(m, "00") + format(d, "00") + format(c, "0000")
else
void
end

I created this command in a browser (from yours template) and works propely but is not the same in mac app: the field become empty.

Any idea?

Tks

bye