The activation code is the latest - F5CF-8A53-B979-CD50. Offline activation was also attempted, but it didn't work either.
Here is the log:
Activating NodeLocked License F5CF-8A53-B979-CD50, Number Of Licenses: 1
Status: 4, Creating request
Status: 5, Request created
Status: 6, Context created
Status: 7, Connected to remote server
Status: 0, Error
ERROR: flxActAppActivationSend (50018,41145,32)
Connection to FlexNet Operations Server failed.