They seem to be facing problems at the moment users of Facebook, of Instagram, WhatsApp and Messenger. The websites of the services are not working which shows it as well downdetector.
"Unable to access this site" is the message that visitors to the above pages have been seeing for some time.
There does not appear to be any official update at this time, but all pages displaying Facebook service status display downtime.
The problem seems to exist not only in Greece, but also in other countries around the world. We are waiting for developments, or some official announcement, that justifies the problem.
We're aware that some people are having trouble accessing our apps and products. We're working to get things back to normal as quickly as possible, and we apologize for any inconvenience.
— Goal (@Goal) October 4, 2021
We should mention that there was no prenotice for the downtime, which means it was not planned by the company.
The company after the celebration published the above tweet.