Several users in the United States and Europe late Monday, and on Tuesday, reported that Facebook Messenger did not work for them.
According to DownDetector.com, the portal that tracks the outages occur in the digital world, thousands of Messenger users could not receive messages, log in and connect to the server.
The disappearance began after midnight and continued hours before the Messenger service returned.
Facebook has yet to disclose the reason for the break.
"Messenger is generally confident, but there were recent problems, with four interruptions only in September," says Forbes report.
The flaw came a day after Facebook introduced the new updated Messenger, which will allow over 1.3 billion users to delete sent messages from various topics, 10 minutes after sending.
Facebook also tests a feature called "Watch Videos Together" on Messenger, which will allow simultaneous viewing of videos via group chat on different devices.