Sorry to hear that, but you have a few choices.
The first is to wait it out for a day or so. I have experienced this on several occassions - the "fix" doesn't fix anything. While this usually doesn't work, take a few minutes to reboot the computer, open the client, and make sure the client shows "Connected to Symantec" in the lower, left-hand corner. Go to Settings and run the network test - make sure it finishes successfullyl. Sometimes there is a temporary disconnect between the client and the cloud.
The second, if that doesn't work, is to contact Tech Support and explain the circumstances. I can practically guarantee that you will not like what they will tell you. The stated course of action for uncommunicative agents is to use the hostedendpoint.spn page to uninstall the service, reboot the computer, then find computers with no service, and reinstall the service. Depending on processor, disk, and Internet speeds, this can take between 30 and 120 minutes. Make sure you run the Definitions update to ensure that things work properly.
If that still doesn't work, you will need to delete the computer from the cloud portal, uninstall the software from the desktop (reboot), then run the two Tech Support-provide clean-up utilities (reboot), and download a completely new installation of the product.
Good luck, and hope that helps!