Minecraft not showing up in the Microsoft Store?

Hi

I once bought Minecraft in the Microsoft Store (pc) and now I want to play Minecraft on the new Series x, but the game is not displayed in the library.

is there any trick or do I have to buy the game again?

Minecraft can't be bought on one device and played on the other, even if you want to play the Bedrock Edition on both devices.

You have to buy Minecraft for every single device you want to play it on.