Every flight I look at and attempt to find availabilty to upgrade using miles comes up in red 'There are no flights available for upgrade" I have tried dozens of dates..close to departure and months away and many city pairs. Am I doing something wrong..is it better to call the Elite Desk and have them look? I'd love to use some of these miles I have accumulated since elite upgrades are few and far between for Silvers.

Can anyone enlighten me? Thanks..

Susan