I need to remove my store credit. Thank you!

Here are two methods to remove all your Apple ID balance:

Option A:

This is from an older version of an Apple document but it still works: "If your store credit is less than the cost of a single item on the iTunes Store, App Store, or iBooks Store, you can add a credit card to your account [how to add a card --> https://support.apple.com/HT201266 ]. When you buy an item, you will use the remaining store credit and [the remainder will be charged] to your credit card." This will not work if you do not still have a credit card from your old country.

Option B:

"If you don't have a credit card, contact iTunes Store support." Apple will remove the balance and keep it.

Click here --> https://support.apple.com/choose-country-region/media-services Select an option and keep on working your way down the menu until you get to one saying your "topic isn't listed". This will present you with support by chat or telephone call.

Or call Apple Support --> https://support.apple.com/HT201232

References:

Read this link for full information about requirements for changing store country:

Change your Apple ID country or region - Apple Support - Apple Support - https://support.apple.com/HT204447