[Sandbox] Auto-renewable subscription available to purchase for regions that restricted in availability setting

I'm working on an application that will include auto-renewable subscription functionality. I'm trying to restrict a few products within a group by using the availability option, for example, only for the US.

However, for a sandbox account with the Germany region, these restricted products are also available to fetch and purchase using StoreKit after providing their IDs through SKProductsRequest.

I tried another scenario where I fetched only products from this group that are available for the sandbox account region in my app. However, after purchasing one of them, in iOS settings on the sandbox account management page, I see a subscription group with all subscriptions, including restricted ones. This means the user is able to purchase them from this page.

Could you please advise on an efficient way to restrict my subscriptions per region? Or maybe this is only a sandbox issue because, according to the documentation, these subscriptions should not be available for restricted regions. Thanks in advance!