Booking.com booked incorrect date!

Last night my wife made a booking for a resort, Riverdance in the North West, for the one night of 17th June 2023 (Saturday). This morning when I got around to schecking the booking I saw it was for the night of the 18th June (Sunday).

My wife is adamant that she booked for the 17th. Therefore that the booking was incorrectly allocated to the 18th!

Seeing as it was impossible to stay for the night of the 18th I requested a cancellation and refund. It was cancelled extremely quickly on Bookin.com's side, I was notifified that I would be refunded only to find out that the refund was R55.26 out of R685.26 - ie the cancellation fee was R630.00. Not happy.

PS I notice that Booking.com does not have its own email address that one can write to and that it has never responded to any issues raised on Hellopeter!