title: TestFlight in-app purchase still use sandbox account
body: <p>I've read the articles/documentation/threads about the in-app purchase process in the TestFlight release.</p>
  <p><a href="https://developer.apple.com/forums/thread/49940" rel="nofollow noreferrer">1</a>, <a href="https://apple.stackexchange.com/questions/196372/testflight-in-app-purchases-sandbox-user-still-needed-after-passing-beta-review">2</a>, <a href="https://stackoverflow.com/questions/43316718/sandbox-account-for-ios-test-flight-beta-testing">3</a>,</p>
  <p>They will always say that the app will use our real Apple ID but will create a sandbox environment for it. <a href="https://developer.apple.com/forums/thread/115031" rel="nofollow noreferrer">This one</a> though, is a bit different. It kind of confirms my situation right now.</p>
  <p>It's either I don't understand that clearly or something wrong with my account setup. I always got the popup to use the sandbox account on my phone.</p>
  <p><a href="https://i.stack.imgur.com/Jb4cF.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Jb4cF.png" alt="TestFlight in-app purchase" /></a>
  <a href="https://i.stack.imgur.com/0E6e4.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/0E6e4.jpg" alt="AppStore Sandbox accounbt" /></a>
  Could someone really explain to me what's happening here? I</p>