Carl's Jr. review: Staff refused to take buy one get one receipt coupon with survey code completed

I have been going to carl's jr at 41st and yale in tulsa for 2 years, 3 times a week. I do utilize the receipt survey to get the code for a buy one, get one breakfast coupon. As usual today, august 23 at 645am, i ordered the 2 breakfast sandwiches, advised i had the receipt with code at the time i ordered. I have not had a problem in 2 years with this. Today, the gentleman at the window claimed to be the manager. He gave me back my receipt and told me he could give me the discount because he couldn't access the special discount area. I ask for a supervisor as i was a regular who uses this coupon every week. He said not today. This should not be problem since it is your survey reward to your customers.