Akim-o

Hello ~If you are trying to zero your balance before changing regions…you may purchase an item from the App Store for more than your balance and the remainder will be billed to your credit card on file thus zeroing your balance . You may also go to lower left hand corner and click on Support and they can zero it for you or…

Contact Apple for support and service

Also if you are changing regions take a look through this article as well…

Change your Apple ID country or region - Apple Support

~Katana-San~

If you have a remaining Apple Account balance left, which you can not spend, you can give the official Apple Support a call and ask them to clear your balance.

You can select the phone number for your region from the drop down menu on this Apple Support page:

Contact Apple Support - Apple Support

You could also spend the remaining balance to buy an app or content from Apple, which costs slightly more than the remaining Apple Account balance, so that your secondary payment method will be used to charge you for the rest of the payment.

I would also recommend to have a look at this related article, to make sure you have completed all other necessary steps:

Change your Apple Account country or region - Apple Support

Welcome and thank you for reaching out. 🤗

1. Purchase something from the App Store at a cost greater than your balance. This is the quickest option.
2. If you are unable to spend the remaining balance, then contact Apple Support to request a reset of your account balance to zero.
3. If you need to change your region, then click ▶︎ Change Region for step-by-step instructions.

Good luck! 👋🏼😉

Smiliñ 😎 Brian | Community Volunteer