We've had multiple clients get an appointment confirmation for an online appointment they made but then the appointments were deleted by Phorest or "Unknown User" because of an error with the booking without notifying the guest or us.

Most recent experience we had a guest who made 2 bookings a minute apart from each other, but because the paid appointment was made at 8:53, and the incomplete booking made at 8:54, the system took the status of the most recent booking, cancelling those appointments. The guest came in for the services that were "confirmed" via auto response but not on our appointment book and the service provider was booked with another guest.