Games removed from library despite owning them!

i will be honest here a little frustrated that i cant just play the games i have outright purchased, Today it was Battlefront 2 i have played it not too long ago and today went to load the game and says it has been removed if i want to add it to my library i have to go to the store and re purchase it so i cant play a game i had just played maybe a week ago and this isnt the first time this has happened