I need to cancel a Reservation

go into the Reservation, then click 'Request to cancel'.  The guest confirms and it comes back to you.  

Hi Michael 

As per the Partner Dignup GSdT ( aka T&C , bookings are auto confirmed based on your calendar showing availability;

and should the guest contact BdC and not you, after being told no availability;

BdC may relocate them and then bill you for it.

So with that said What I suggest and has worked many times in the past is :

• Deal directly with guest to keep them engaged  
• Create a Message Template for notifying Overbooking Guests, to succinctly inform them there is actually no availability for these dates, and you must cancel their booking. Dont over share/ padding /waffle. Notify them their prepaid [if any] amount will get refunded once they receive the confirmation notification and click on the action link to trigger it.  
• .Once you have informed them, now open the reservation details page and choose Request Cancel on the right pane, lower area.  
• Choose Option 2, and notification by system is sent out. THere is a link in it for them to click on to confirm.

Kind Regards, Be Safe Be Well

PS: your partner profile is still  incomplete, missing listing URL, please update to it as it can at times greatly help us help you when the time comes.

Guide : How & Why Add your Listing to your Partner Community Profile

BdC Support Team HowTo: Dedicated Partner Contact Options - Visual Guide