Unable to play any DLC for AoE3:DE

I recently bought The African Royals as well as the United States + Mexico Double Pack from the Xbox Store, but when I try to use them in-game, they are locked out as if I don’t own them.
When I click the link next to the Civ in-game, it opens a small store window as if I was about to buy it, then changes and says I already own this product.

I’ve tried uninstalling the game and reinstalling it, but that didn’t work. When I tried it the first time after reinstalling it, it said it was unable to sync my data or something along those lines.

I have confirmation of my purchase, the store page says that I own them and they are installed, so I’m stumped…

I’m playing the game through Xbox Game Pass, so I don’t actually own the game, just the DLC’s. Is this the problem?