This problem have existed for years and continues to exist right now. I edit lots of HDV sequences and I get this very often like once in a fortnight or weekly at times. I will have to sign out and sign back in at times after signing in all the softwares will appear as trial hence I pay every month in this world. Shame on adobe-software! Some Adobe remote technicians pointed that the activation might be bloced by Antivirus softwares. But that being said I remember that the Creative Cloud will only need to check activation once every 90 days or less I don't know. I think it does check activation on a daily bases or every time you launch it.
VERY ANNOYING.