Article summary: A cancelled booking stays in the closure ("Accounts" tab) when its room line is still in the guest's billing account. To remove it, delete this line from the billing account.
The question
"How do I remove from the closure a Booking.com reservation cancelled on Booking.com and in Reservit?"
The short answer
Delete the room line left in the billing account. In "Close", "Accounts" tab, click "Access to account" for the guest. In the account lines, tick the line of the cancelled room, click "DELETE ROWS", then "YES". The account disappears from the closure.
Why does the booking stay in the closure?
When a booking is sent to billing (prepayment, deposit, virtual credit card from the channel, etc.), its services are copied into the guest's billing account. Cancelling the booking frees up the room, but does not remove these lines from the account. The account therefore stays "debtor" and the "Accounts" tab of the closure keeps displaying it.
Warning: only delete service lines (room, extras). If cancellation fees are due, invoice them. If a payment had been received, it stays in the account: refund it or keep it according to your cancellation policy (see How to Refund a Payment via Terminal in Reservit PMS).
Step-by-step tutorial with screenshots: How to Remove a Cancelled Booking from the Closure in Reservit PMS (Billing Account).