@Abrasha-and-Maria0
Thanks for reply and spelling correction!
Firstly, I have never used Instant Book. I'm a live-in host and it's not remotely suitable. I need to screen every enquirer to my satisfaction.
There are many Hosts on this forum who do use IB and so can better advise you.
However, a 'Work' or 'Business' booking as it is variously called is permissible and does not infringe so called 3rd Party Booking. So as long as you are content to accept such bookings then no problem.
If a private person books for a 3rd Party via Instant Book, then best phone Airbnb Customer Support and request CS cancel the booking and contact the Booker.
Do not Cancel it yourself as you will face the penalties: automated Cancellation on your profile, financial penalty of $ 100, and loss of Super Host. (Though as of July 1st 2019, Airbnb changed the ruling to allow 1 Cancellation per 100 bookings per annum.)
I understand IB hosts are permitted 3 cancellations per annum, but I'm not sure how it all works because CC contains quite a lot of complicated cases. So if in doubt phone CS.
The gray area manifests in the type of booking you took for your current guest. Indeed, most 3rd P.B. requests are on behalf of family or friends. Many hosts do not see a problem with it. Airbnb will also process the booking, but will not apply their Host Guarantee (for what its worth).
There are various ways to address it. The following are my experiences as non IB Host. So I either receive an Enquiry or Reservation Request.
i) My initial response depends on whether I will even contemplate the enquiry / request.
If so, I will kindly suggest the person who will stay open their own Airbnb account and so make the booking in their own name.
If not, and a pre-paid Reservation Request was sent, I kindly ask the person to 'WITHDRAW REQUEST'. If they decline I phone Airbnb CS and ask them to Withdraw the Request (i.e. Cancel).
ii) If the prospective Booker makes a case that it's difficult for their relative or friend to open their own account, and I am still willing to consider their request, then I follow the directive once given me by a Customer Service Rep: Airbnb will not apply its Host Guarantee and therefore I the Host am obliged to request the Booker accepts liability in any eventuality.
In the past month I've had two such cases.
In the former case, a father in China sent a request to book on behalf of his daughter in UK. I noted the father had been liberally doing this for 3 years with 16 Reviews, more than half on behalf of one family member or another. I phoned CS and the Rep took control of the situation. She immediately Cancelled the Reservation Request and contacted the father.
Within an hour the daughter contacted me in person having just opened her own account. It also meant that she must be at least 18 years old and so eligible to open an Airbnb account. I accepted her booking.
In the latter case, this week as it happens, a young man living close to my home, wanted to book on behalf of his father. I suggested the father open his own account. The son replied immediately that he would inform his father to do so. However, half an hour later the son contacted again apologetically saying his father couldn't easily do it, and he couldn't easily help his father who was flying shortly from New Zealand. -- Consequently, I accepted the booking conditionally. The son should arrive with his father and accept liability in any eventuality. The son was happy to do this on the Airbnb messaging system. He arrived with his father and everything was fine.
Finally, the biggest problem are Undisclosed 3rd Party Bookings for Personal Travel. In other words, the Booker does not inform the Host at the time of booking that someone else will stay in the property.
In some cases, Booker might inform the Host sometime after booking and before arrival of 3rd Party. - At that point apply the above solutions.
Trickiest of all, if it's not disclosed at all, but the Host becomes aware of it at check-in (most likely if Host requests ID and discovers it does not match the Booker). Host can then refuse entrance and immediately and contact Airbnb to Cancel the booking.