I had something similar. I had booked a hotel and cancelled it later on. A few years later an award booking was made at that hotel. I received email confirmation of that award booking a day after the check-in date. Points weren’t taken out of the account until the check-in date so i was unable to cancel. I called Marriott to cancel the reservation but that couldn’t be done since they said someone was actually staying there. Marriott said i made the reservation even though they told me the booking was made earlier in the year to which i said, the points weren’t taken out at the time of booking and neither did i get confirmation which would have allowed me to cancel. Felt like an inside job but Marriott blamed me for the whole thing happening.