Xambo

Have you tried logging in both accounts in one console? 

if that doesn't help then i guess it is worse in your case as neither of you have it as owned in library. 

i still believe the problem has to do with family accounts. 

Not sure how many people have the same issue. Since we cant even buy the game again (even though we already bought it) because the store says already owned, the only solution is for mojang or xbox to refund the purchase therefore not owning in it. Then purchase it again from store to reset the ownership rights, or by giving us a voucher. This could solve our problem individually . 

I found a temporary work around. The issue arises, at least in my case, if you have a family account or bought the game for a family member or a friend. After the last update the system now confuses the real owner that bought the game. 

Even though I bought the game twice (2 copies and have the receipts) for me and my son. Now it only thinks my sons owns under his account. Also, even though we both show ownership in the store. But under owned games library he only has it. I dont.

So what I did is logged both our accounts (have to be both logged) into my Xbox console. Also I made this console "my home xbox" under settings. It now works for both our accounts. 

Twitter Mojang Support told me to come here and try to find a solution. But I couldnt find much about this specific issue so I created a new one.