Restart Final Draft and the error message may not recur.
If this doesn't work, restart your computer and the error message may not recur.
If this doesn't work, see this article: When I try to activate Final Draft on my Mac, I get this: "Activation server failed with the following error message: Error:[0, 0, 0]***Error code was: 0"
If the solutions in the article don't work, please open a ticket with our technical support department:
https://www.finaldraft.com/contact/contact-technical-support/
6014
https://fd.support/3CfG6th