Originally Posted by estnet

Maybe because the sale ends for stays until July 31?

"Save up to 35% at participating Marriott International Hotels and Resorts in Thailand, Vietnam and Cambodia. Book now and enjoy your next getaway!
To make you booking visit: https://bit.ly/2Um0IbT
Valid for bookings made: 18 - 24 March, 2019
Valid for stays from: 19 March - 31 July, 2019"

HOWEVER - Just for fun I checked one night May 31-June 1 - the "special" rate was 4500 and the member prepaid was 4275!!!! So i guess the sale isn't a sale????