Booking.com Missing PIN Code: How to Cancel Booking Without PIN

I made a hotel reservation through Booking for Motel 6 Youngtown Sun City. I booked it last night for a check‑in on August 24 and check‑out on Saturday. I now need to cancel the reservation but I do not know how to do it properly through the system. When I called customer service, I was answered by an AI system that asked for my confirmation number and PIN. I have the confirmation number (5441976208), but I cannot find or access the PIN anywhere on my side, so I was unable to proceed with the call or manage the reservation. I am requesting your support to help me find or recover the PIN linked to my reservation number 5441976208, or alternatively to assist me directly with my reservation so that I can manage or cancel it as needed.