Hello Hayyan Asim,
You can freely change region, however, please note that the subscription is only be able to purchase if the account region, the PC region and subscription region match.However, as I see here, the issue seems to be with the payment method instead. You said your uncle has cancelled the subscription on his card, which I assume that you are using a new card to purchase. This is quite common for new purchases in gaming platforms to fail the first time and require verification. In this case, please try to contact Xbox Support for more information about this transaction, as the message said.
Thank you for your understanding.