Removing my Store balance so I can switch countries

Hi, I have $7.01 left on my App Store balance and I want to get rid of it so I can switch to the Store in the country where I now live. I followed the advice of trying to buy something with this credit, but when I try I get a screen asking me to take a picture of the Gift Card or enter the code manually, but I redeemed this gift code nearly 10 years ago and no longer have access to it. So how can I use or get ride of this balance?