The link you followed will bring you to this page:

https://www.regione.lombardia.it/wps/wcm/connect/6ebe1e37-1568-42d2-9876-bd58c59ca209/FAQ_ACP.pdf?MOD=AJPERES&CACHEID=ROOTWORKSPACE-6ebe1e37-1568-42d2-9876-bd58c59ca209-nw1.G6Y