There is too much grey area in this to make a strong case for either side. (not saying you did) but you could just have easily cancelled the reservation yourself for any unknown reason (there would be many, believe me) and then decided to show up instead because it worked out or whatever.

Seems to me that you need to let this one go, as employee time will be better spent. You would have got an email confirmation of the cancellation to your email on file as well informing you of the cancellation at which time you would have called up immediately to inform them of this error. I book 200 hotel nights a year and have never heard of this happening or had this happen inadvertently.

Again, not calling you out or placing the blame on anyone here - but you were placed at a hotel for the night and just chalk this one up as a bummer on whatever end actually happened.

There is no proof who/what/where/when/why the cancelled reservation so to look for points and bonuses and stay credits and half credit toward a free night shows me that you are in this just to benefit.

That doesn't sit too well after reading that part. You already know exactly what you want instead of letting the company asses the issue and handle it as they see fit.

Stay well,
T