Hi, to change the country on the Samsung Account, please follow the below steps:
https://account.samsung.com Sign in >> Contact us >> Fill in request form with title 'Request for change of national information'.
Please note that:
If you change the account country, then all the history of what you purchased in the previous country will disappear (e.g. Galaxy Store, Points, etc.).
This is not a Samsung account limitation.
Purchase details are managed by each country under separate service policies.