The subscription is still valid even though you have cancelled it so it will not renew. To cancel the use of the subscription immediately you will need to contact Apple directly.
Contact Apple Support - Apple Support
You should also be aware the a valid credit card may still need to be on file to download apps, even though it will not be charged if you have funds in your Apple Account.
If you can’t download or update apps on your iPhone or iPad - Apple Support
The region of the payment method must match the region of the device. This is how Apple determines you are using the correct App Store for your region. In the past, some people would fraudulently change the region on their device to download app and use services that would normally not be available to them in their region and this is one way to prevent that from happening.