I'm trying to use the triple Rapid Rewards credit promo code posted in the Southwest forum for an upcoming reservation in Green Bay. But, I get an error message when doing so, stating that the PC code doesn't qualify based on the dates/times I've selected. However, I double checked and all should be copacetic. The double credit promo doesn't work, either.

Is this because GRB is a franchise location? Also, I noticed I only get 200 miles per rental day. Though, at $21/day I guess I can't complain too much.