The timing of receiving your refund is affected by if you cancelled within or later than 6 days after you made your initial purchase:
If you cancelled a session within 6 days from initiating the purchase, you are still in a "reserved state", and your refund is processed within one day.
If you cancelled a session more than 6 days away from initiating the purchase, you are in a "charged state", and the refund could take 2-3 days (depends on card and bank)
Court bookings (pay your part) — lead booker refunds
If you are the lead booker on a court booking, the full court cost may have been reserved or charged to your card while waiting for other players to join and pay their parts. After the session ends, Nettla calculates the final split 4 hours later and refunds any amounts covered by joining players back to the lead booker.
The timing of that refund follows the same rules above: if the booking was made less than 6 days before the session, the adjustment happens quickly as the reservation simply reduces. If the booking was made more than 6 days before the session, the full amount will have been charged and a real refund will be issued, which may take 2-3 business days.