Trados license

I have Trados Studio 2015.  From one day to the next, I can no longer use Trados.  When I enter my license number, I discover that my account indicates 1 user, 1 in use and available 0.  I try to enter my license when I open Trados, but I receive a message saying that activation has failed because it has expired. Is this normal? Thank you for your attention. Ghislaine