Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Refer to https://learn.microsoft.com/en-us/answers/questions/5317930/error-convblockcurrencycountrymismatch
ConvBlockCurrencyCountryMismatch indicates that you purchased the Microsoft 365 Basic subscription from a different region/currency as your current region.
Also, please understand that you cannot upgrade a Microsoft 365 Basic subscription to a Personal subscription. You will need to cancel your Microsoft 365 Basic subscription and purchase the Microsoft 365 Personal subscription. This will likely resolve this ConvBlockCurrencyCountryMismatch error.
Make sure you have the correct region set in Microsoft Store as well as on your device.
Change your language and region in Microsoft Store online: Go to Microsoft Store online (https://www.microsoft.com/store). At the very bottom of any page, select the World icon to choose your language and region.
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hth
Marcin