Try pressing LT+RT+X it hides and shows ready to install games or games you picked to hide in the ready to install section

or

Log into another account on Xbox and then log back out of it and then log back into your account

Give that a try and let me know

I have this same problem with a friends account and Ark. Also won't let me use his live even though I've set his account as home and have downloaded other games before. If you figure it out, please let me know how.

I believe if you find the game in the store which should be appearing, it would come up as already purchased and you then have the option to reinstall from the store page

Well, I've tried both of the things which were recommended by Power-ade, but nothing's happened. My cousin told me it happened to him for some time too, even though he bought the game.

I go into the Store and it only asks if I want to buy it, still no solution to this issue.

Weird, if the home Xbox was setup correctly it should appear under Ready to Install. If its not I'd get them (account holder) to login to their account on account.microsoft.com then go to account.microsoft.com/devices and see if your console is set to the home Xbox. If not MS will probably have to reset it and try it again.

If it's glitching for some reason I'm pretty sure there is a download to home Xbox option via Xbox.com store if your logged into their account. Might force it to start downloading on your Xbox.