Unable to Make Purchase on Apple Online Store and Refund Apple Account Balance

I am trying to order an ipad Air and an Apple Pencil on the Online Apple Store (with Education Pricing). However, the website rejected pretty much every form of payment I had available! Even when I resorted to purchasing gift cards and redeeming them to my Apple Account, the system said "payment authorization failed" when I tried to use my Apple Account balance.

I called customer service and Apple Support many, many times, and the sales team tried to make the purchase on their end. I also physically went to my local Apple Store and attempted to make the purchase with its manager at my side. Even so, my order kept getting declined due to the same problems. This was all despite the fact that according to my bank, there were no security issues with my debit card, and according to Apple Support, there were no holds on my Apple Account.

Therefore, I tried requesting a refund on my Apple Account balance, as the only option seemed to be physically going to the Apple Store and purchasing the aforementioned products via the store system with my debit card. However, the Apple Support team claimed there was no way for me to refund my Apple Account balance. As a result, hundreds of dollars are stuck in my Apple Account, unable to be used in a meaningful way. This is basically a lose-lose situation for both me and Apple.

Could anyone please provide me with a clue on navigating or resolving this mess? The last thing I want is hundreds of dollars of my and my parents' money being stuck in limbo, practically un-usable. Thank you.