Location was Toronto Pearson Airport departure level. I approached the counter to order, showing a coupon for my order. My order was taken and when coming time to pay I was informed the coupon I had was not valid due to the location not having the proper equipment to scan the coupon. I was asked to download their Subway app and make the purchase online to get the discount. First of all, there is absolutely No signage stating they cannot accept cupons, secondly, I had shown the coupon while placing my order with no mention of not being able to accept the coupon and thirdly I only had enough cash on me to cover this meal, and fourthly, I was on a time crunch and unable to add more time to download their app and place my order through the app. So they decide to either discard the meal which was already made, or give it away,( I cannot imagine they would attempt to resale the meal.. but then again, you never really know ), as opposed to offering some other form of discount and informing me not to let this happen again, I work in the area of this location after this experience I will no longer be a customer of them. I advise all travelers to be aware and verbally ask any questions Before placing your orders. I am extremely disappointed in this locations customer service.