I want to make zero balance in my account to change region

Yes, this is a known issue. You have two options:

Option 1.

Zero our balance out by making a purchase. It doesn't have to be the exact amount. It can be something slightly more expensive. You would have to have a debit or credit card associated with your account to do this. When you purchase the item, it would use up the remaining balance in the apple account first and charge the rest to the debit/credit card you have on your account. This will leave you with a zero account balance and you can move forward with the region change.

Option 2.

Contact Apple to have them help you with this. You can do this via https://getsupport.apple.com

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…

Apple Support

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~