Have you elected to choose the 5e Compendiums on your game's settings page? A given game doesn't know if it is a 5e game or a pathfinder game, though it will ask you if you want to use the default compendium of your sheet. If you can see other purchased 5e content, but not Xanathar's content, then something is likely wrong, and you should contact <a href="mailto:team@roll20.net" rel="nofollow">team@roll20.net</a>.