Change Region

You'll have to contact the official Apple Support about that, use the link below as a start:

...

• If you still can't change your country or region, or you have less store credit than the cost of a single item, contact Apple Support.

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copied from: Change your Apple ID country or region - Apple Support

—First—

Make a request to zero out any remaining balance on your account by contacting Customer Support by phone or chat:

• Call Apple Support at 1-800-APLCARE. 📞
• International Support. 🌐
• Contact Apple Support. 📝
• Chat using Messages. 💬

—Then—

Click ▶︎ Change Region. 🌐