Rollback not working

I've noticed in the past few weeks that rollback option doesn't really work now, both by using the option in the Escape screen and by using a command (I am hosting the server and have access to commands). I tried rollbacking both when playing alone and with someone and it doesn't make a difference. The only semi-reliable way of rollbacking that I know now is to exit the world and rollback from the saves screen in the settings menu.