Norton 360 sign in

Every time I try to log in to my Norton 360, it will not accept my sign in & password. I get a temp password, change it and the next time I try to sign in with the new password, it will not accept it again. What do I do?

Every time I try to log in to my Norton 360, it will not accept my sign in & password. I get a temp password, change it and the next time I try to sign in with the new password, it will not accept it again. What do I do?