@Lina0 - first of all, if you are the co-host, and set up as the co-host properly, then cancelling a reservation on behalf of the host does not affect your Superhost status. You should read up on these nuances. Second, a "maximum" is inherently a house rule. If the house capacity is 6 and 8 show up, they are in violation and you can reach out to Airbnb to have the guest's reservation cancelled for breaking the house rules (don't do it yourself - call Airbnb!). Third, add a line to your house rules that states that guests not identified on the reservation will be charged an additional fee (this covers a group who book for 4 but show up under the maximum with 6).