@Maggi450 The bookings are down to you to discharge and you will get paid for them. The 'proper' way to deal with this is for the new owner to set up an account and then for you to write to all the guests asking them if you can cancel and transfer their bookings to the new owner. I think, but am not sure, that selling allows you to cancel free of charge.
The less proper way to do it is for the new owner to set up an account and block currently booked dates. You block unbooked dates in your account and just transfer the money to the new owner as they discharge the bookings. Clearly this way leaves you at risk of the new owner doing a bad job/letting down your guests and the new owner at risk of not being paid / having to build up their reputation as they will have no reviews.
No easy answer here I am afraid