Totally weird. cause my original rental said the coupon was accepted. Moreover, they charged me $335 for the rental, even though my original rental had said $285. The way it happened was that it had my name on the preferred board, but it said, CTR. I went to the counter and a lady helped me out.
Guess next time when I make this reservation again, I will be sure to ask about the coupon...
But the e-receipt says that I rented a Class E and was charged a Class D.