Booking.com Took All My Money Even Though I Canceled in 15 Min

We made a reservation on May 27th and had to cancel it just 15 minutes later. We didn’t use any service of the property, nor did we cause any inconvenience. We even canceled well within the same hour, thinking it wouldn’t be a problem. Yesterday, we found out that the property has not refunded the amount of $3,500. This is a huge financial loss for us, and it feels incredibly unfair. We contacted Booking.com, but they didn’t help us at all. How is this possible? We didn’t stay at the property, yet the full amount was taken from us. We trusted Booking.com when making the reservation, but they completely failed to support us.