@Mitch4
I had an experience similar to this.
First and formost is the booking showing as confirmed in your dashboard. If not you will not get paid or be covered by airbnb insurance.
As far as I can work out sometimes for a variety of reasons a booking doesn't fully process through the system. The calander holds the dates but no confirmed booking eg insufficient funds in the guests account.
If this is the case I would be careful. If the booking hasn't confirmed then they will not have recieved your address and contact. However, I do believe the confusion around this situation has been used to gain admittance to airbnb accommodation without facility to pay the host.
If its still unconfirmed you could attempt to get airbnb to remove it from your calander.
Regards
Janice