Well it worked once again only in the asteroids but in the flappybird no. I think the problem is that the classes dont connect to each other and i dont know to fix it

You should only deal with the UserInfo class at start-up (to initialize high score, if possible) and when a potential high score is achieved. A field to hold a UserInfo object can be maintained in your World subclass (MyWorld?). It should be checked for it not to be null before working with it (like when checking the high score value of the current user/player). If a new high score is achieved, set it the the score of the UserInfo object, check for storage availability and save, if possible.