A Member is eligible to receive Points/Miles for staying at participating Marriott brand hotels or Ritz-Carlton hotels for his/her room and up to two additional rooms. At least one of the rooms must be reserved and registered in the Member's name and the Member must pay for all rooms, which payment arrangement must be requested at time of hotel check-in.
Do a search and you'll find several "why didn't I get points/credit" for this reason.