Mandalay Bay Free Room reward

Has anyone used the free room at Mandalay Bay? It appears that there is a $15 fee to book this over the phone?
How do you book this online? I also cant see any blackout dates.

Any help would be appreciated.

Thanks

Chuck

Buy the reward, click on ,click to redeem. It will take you to the mlife.com site. If there are no rooms available for your dates. Cancel the reward and your points will be refunded.

I recently booked two nights at Mandalay Bay for February. The calendar showed the dates as eligible but when I clicked the dates to book on line, it wouldn't let me saying they were not good dates. I called them to book for me, explaining the trouble I had, and they took care of it for no charge.