Skype, Microsoft's online telephone and video service, revealed Monday that there is an issue affecting various users worldwide that makes users appear permanently offline.

Specifically, the issue makes various users and their contacts appear offline, even while they're logged in. As a result, users have been left unable to make calls, with their contacts being unable to call affected users in return, according to The Wall Street Journal.

The company became aware of the issue around 2:00 a.m. EST when users around the world, including major areas like the U.K. and Hong Kong, flooded Twitter and Facebook with complaints saying they had been left without service.

"Skype not working in Japan," said Sachiko Sasha M., on Skype's Facebook feed.

"Hong Kong cannot login too," added Josephine Wong, another user.

Skype noted that even though affected users will be left unable to fix their status, they still be able to use Skype for instant messaging and Web services, according to Business Insider.

At first, the company stated that they were working on a "quick fix", but later revealed they identified the problem.

"We're in the process of reconnecting our users, and focused on restoring full service. The issue did not affect Skype for Business users," it said in a blog post.

While working on the problem, the company issued an apology for the inconvenience the incident has caused.