What are the options if Symantec PGP Keys are revoked?

Hi,

I am a newbie so pardon my lack of knowledge. We are using Symantec Drive and File Share Encryption in our environment. Key Mode is SKM. We didn't changed the default of Auto Key Renewal of 2 weeks and now one of the user's keys are expired. How can i change the validity of those keys and re-enable them?  Basically i want to know what are my options and what to do once the user's keys are expired? Thanks.