Make sure you review your bill prior to check out. I recently had a reservation through the Fine Hotels and Resorts program offered by AMEX, and to my surprise, I didn't get the credits (close to $200) that were offered to me as benefits. I did everything that was stated to me by the front desk upon check in, and charged it to the room. However, come to find out a couple weeks later when reviewing my CC charges, I never got the credits that were promised to me.
I was never told to remind them upon check out and I never thought that I had to second check that I was given an amenity that was entitled to me...
You would think the Mlife or MGM resorts would be on top of their customer service...I never had these issues with the Cosmopolitan of Las Vegas Resort.
From now on, I will review every bill from the MGM resorts- and that's even if I have to stay with them at all...no stars deserved!...if I could zero, I would!