Beforehand: This might not technically be a launcher issue, but no Idea where else to put it.
Essentially, those who own the bundle can't get access to Minecraft preview. When you click on the link to the Microsoft store/Xbox page, all that you see is either a get with game pass button with Xbox or no way to access it in the store.
Closing as invalid.
For any account or purchasing related issues, please contact Minecraft Customer Support directly, as we cannot assist with those here at the bug tracker.
Quick Links:
📓 Issue Guidelines – 💬 Mojang Support – 📧 Suggestions – 📖 Minecraft Wiki