Only applies to bookings made through Booking.com 

current position
Guest has booked a room via Booking.com and a payment has been made - now the guest changes this booking at Booking.com (causes almost a cancellation and new booking in our system). 

Already made payment transferred to the new, active reservation (booking of Booking.com)

1. Start DormBook
2. Enter the new reservation number 
3. From "Remark" (remarks) copy the old reservation number 
4. Open the left window (Edit reservation group) by clicking on the arrow (see below) 
5. Enter the copied number and click on "Add reservation" 
6. At the bottom of the tick box, tick "Show all" (to make the canceled booking visible) ("Due" should then show the "minus amount") - this is then transmitted (does not necessarily need to be selected) 
7. then set Amount to 0.- (if there already 0.- in there stands, then above a reservation select) 
8. Click on «Paid» (type Payment is no matter) - enter text: «Payment transferred from canceled booking to Booking.com»