San Francisco, Nov 11 (IANS): Several Twitter users on Friday reported that the new $7.99 Blue subscription service suddently disappeared from their iOS app, as Elon Musk claimed the platform has hit an "all-time high of active users".

App researcher Jane Manchun Wong said that Twitter seems to have unlaunched the new $7.99 Twitter Blue subscription.

"Checked with Twitter's API and the in-app purchase for Twitter Blue Verified is no longer listed for production," she commented.

Several Twitter users reported that the option to sign up for the paid Blue subscription service just vanished from the sidebar in the iOS app.

"LOL and now Twitter Blue is gone. Nothing like skipping all testing, market research, ignoring your veteran team members, no A/B testing, and just going live with all new random thoughts you have to the entire population of the largest social media platform," posted Ryan Morrison, commonly known as Video Game Attorney.

Those who could still see the Blue link, trying to sign up only resulted in an error message.

"Thank you for your interest. Twitter Blue will be available in your country in the future. Please check back later," read the notification.

It was not clear why users were not able to sign up for Twitter Blue service which had a chaotic launch.

"Literally like an hour ago you could still sign up for Twitter Blue and now it's gone. Great feature while it lasted though it was the Chiquita tweets that did it for me," another user posted.

Earlier, in an ongoing flip-flop on the future of Twitter, Musk has again brought back gray 'Official' verification badge for some accounts in select parts of the world amid a wave of impersonated accounts that hit major brands along with celebrities in recent hours.

The extra layer of "Official" verification has been brought back to counter such impersonification attempts.

However, these "Official" badges are not visible in all countries and most of the gray badges were visible within the US at the moment.