Latest Update: WhatsApp was back now. Check and comment.
WhatsApp was hit by a big blackout that prevented millions of people from using it all over the world.
Users could not send or receive messages via Facebook, because of a problem with the server. The service now seems to have been gradually restored.
The application does not seem to be broken at the beginning, with chat and contacts that could be loaded. But once a user participated in a chat, the app showed only a "connection" message that was never resolved, so it was not possible to send or receive new messages.
This also meant that there is no easy solution to the problem, as it seems to be on the WhatsApp side. For example, if you close and open the application, the connection message is reset but not interrupted.
The Down Detector site has shown a strong increase in application issues, suggesting that almost no one can connect. Problems are concentrated in Western Europe and Asia, but have been reported worldwide.
There have been relatively few problems in the United States, but this could simply be the result of time zones, which means that many people slept there. Even WhatsApp's Web using the phone connection broke.