I don't know if I am the only one who has problems in this area, we planned a vacation and were going stay at several different Marriott hotels, so we purchased prepaid gift cards. Almost without exception when we go to check out the clerks did not know how to process them. Twice we were billed on the CC# on file along with the gift card another time the clerk asked us if we could just charge the room with the CC on file. The other times we had to wait until the manager was called on the phone or if they were there had to assist us.
I do not blame the front desk clerks because it was not just one or two who had problems,
I blame the management; I think they should train the front desk clerks in this area or if they are training them the need to reevaluate what they are teaching.