If you can accommodate the larger group, great! Loftium doesn't charge additional fees per guest. You can always ask your guest for more details about their party, and, if it's an Airbnb reservation, ask your guest to submit a change request.
If you’re unable to accommodate the larger number of guests, let your guest know that your place isn’t the right fit for their group size, and that you can only host a maximum number of guests, and this is clearly outlined in your listing.
If needed, ask them to cancel their reservation. They’ll be refunded according to the listing's cancellation policy. If they will not cancel please reach out to Airbnb via phone and notify Loftium of the situation as soon as possible.