guest brings unauthorized visitor

[Neo46]

How do I deal with a guest who brings visitors to stay over without asking for permission? 

[Helen3]

If you want to accept the second guest then speak to the guest who booked, say you are disappointed to see they have brought a guest to stay who they have not booked and paid for. @Neo46 

Say that although you have the option to ask Airbnb to cancel , you are willing to work with Airbnb to add the guest to the booking once they have approved payment for the second guest.

If you don't want the second guest there, tell them to leave.