YouTube has been working overtime to fix a huge bug in its system that caused channels to lose huge numbers of subscribers within mere minutes on the video service.

On Monday 6 February, YouTube channel owners began noticing that their subscriber numbers were dropping dramatically. The issue was first spotted by the YouTuber BlackScreenTV, who noticed that his account suddenly lost 1,555 subscribers in just 24 hours.

To prove that there was clearly some sort of error, the user created a video that livestreamed the subscriber numbers of BlackScreenTV, together with five other popular YouTube channels, including Pewdiepie, Drama Alert, H3H3 Productions, iDubbbz TV and Tana Mango.

Pewdiepie soon joined in and began livestreaming the numbers too, and he noted that every "unsub counts as -100". YouTube took a while to respond, but eventually on Thursday 9 February, Team YouTube tweeted: "Yikes! Starting Monday, in some cases, we accidentally started counting two unsubs for the price of one. We're working on a fix!"

YouTube also clarified to another channel owner that the bug only affects how the subscriber count is displayed on a channel's homepage, but not the actual number itself. "No data is lost, and we're working to fix the numbers on impacted channels," Team YouTube said.

YouTube seems to have removed the error now and Pewdiepie has deleted his tweet about the unsubscriber numbers, perhaps at the request of YouTube, but over the last few days, the sight of subscriber numbers falling in real time on websites like Subscriber Counter was quite startling to watch in real time.