Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Unfortunately, as per https://learn.microsoft.com/en-us/answers/questions/5226127/cant-change-country-when-add-a-new-payment-method
When you have an active Microsoft 365 subscription from another country/region, you will not be able to change your country/region.
You need to wait till the subscription is expired or cancelled before you will ne able to make regional changes and purchase a subscription from your current location. This is due to the regional restriction on Microsoft 365 subscriptions.
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hth
Marcin