A few months ago, I accidentally downloaded three livery packs from the Marketplace. I uninstalled and deleted them immediately afterwards. Yet, these three items still show up in my library, even though they were deleted and deactivated long ago. Why do they still appear? How can I completely remove these deleted items from the list?
Surely it can’t be right for all those disabled items to keep showing up there forever?!?
Currenty you can’t remove them.
I believe there is a wish lust to change that, to be able to hide unused items.
..and don’t call me Shirley!
See related wish: Hiding (obsolete) add-ons in My Library
But i don’t have it anymore. I never used them. I uninstalled and deleted these three livery packs. It makes absolutely no sense, to still show it in my library… 
Maybe try to delete the “Content.xml” file (make a backup 1st) and restart the sim, a new one will be automatically built.
I am on ms-store too and it is located in this path:
C:/Users/XXX/AppData/Local/Packages/Microsoft.Limitless_8wekyb3d8bbwe/LocalCache/youruser/Content.xml
Annoying yes, but they show up because you purchased them at some point. Even if you never used them, they are yours to use forever.
Hopefully we can hide them one day, especially the Permanently Incompatible.
Add a vote to the link DementedCorn provided.
