Mastercard complaint: 97.00 stolen from MasterCard

I purchased multiple gift cards years ago for presents, and emergencies. I didn’t have any emergencies, until I left my money clip at home, and pulled out one of the multiple gift cards from my glove box. I was told by the cashier that it had a 3.00 balance on a 100.00 dollar card that had never been used. The cashier checked and watched me take it out of the cardboard casing. It was stated on the front that it had an expiration of 62024. I took it back to the grocery store customer service where I bought it. And they could see on my history that I bought a lot of these cards. They suggested that I call MasterCard. I did and was told that I lost 97.00 due to not using the card. It didn’t state that anywhere on the packaging cover, just the expiration date. I asked about the other cards. and they statt ed that they couldn’t see any purchases. But that I could find the inactivity rule on the back of the card in fine print. I have several others and she rufused the check on any of those. I guess I just get embarrassed if I give them away as a present, or try to use myself. Luckily I had purchased some Amex cards as well. And they are sending me a new card with the whole balance that wasn’t used.