Why Are My Apple Gift Cards Blocked After Trying to Use Them?

I'm having a big problem with some Apple gift cards I bought. I recently purchased 9 gift cards from official Apple Stores in Dubai, including 7 from the Mall of the Emirates and 2 from Dubai Mall, each bought on different days. Despite having the physical cards and original receipts, when I tried to use them to buy an Apple product, my transaction failed, and the cards are now showing as blocked. I've reached out to Apple Support and visited the store, but they said they can't access the system to unlock them. Also, I contacted Dubai Consumer Protection, but they closed my request without helping me. One of the cards was used partially before with some balance left. I'm now escalating the issue to Apple Executive Relations but would love to hear from anyone who's faced something similar or has advice on what I can do next. Appreciate any tips!