How can i reset my appstore balance

Then try clicking on 'The Topic Is Not Listed' and fill in the form to ask iTunes Support to remove your balance

If you are wantiing to change country then you can try contacting iTunes support via this page and ask if they can remove the balance so that you can do so : http://www.apple.com/support/itunes/contact/ - click on Contact iTunes Store Support on the right-hand side of the page, then Purchases, Billing & Redemption

then click what after it? sorry, i just have the same case here