This happened to me over several stays at the Andaz Wall Street awhile back...I actually didn't notice until I called GP about some other points issue (I literally call once a month about points issues, the system is horrible and maybe one in 5 stays is ever right for me), and I noticed the points looked very low for a few stays. The agent looked into it and was able to correct it without me doing anything, but I was a little annoyed they seemed to be aware of the hotel's problem and never fixed it on the customer accounts.

Seems to be par for the course with GP though, the system is full of mistakes, but the agents over the phone are usually incredibly helpful and nice about fixing it....just have to be vigilant in checking your account.