The social network released a statement explaining the failure that happened in April; tweets that were supposed to be closed to “friends” appeared to unlisted people
Twitter disclosed the cause of the bug that left Roda’s tweets visible to everyone. The birdie’s social networking feature works like Instagram’s Best Friends. However, in April, Roda’s publications were appearing for users not subscribed to the friend list.

According to the company, in an email that The Guardian had access to, a security incident that occurred at the beginning of the year was responsible for showing the Wheel of users to all of Twitter. The company did not go into much detail about the incident. But it stated that the glitch has been fixed.
Your Roda is now only open to friends and close ones
Now that the glitch has been fixed, you can use the Wheel at will. Twitter claims that tweets posted on the feature will only be visible to the accounts you’ve added to the list — usually made up of friends or closest people. Now, no strange people sticking their noses in your Wheel.
In the email, Twitter said it is committed to protecting the privacy of people who use its service.
Despite understanding the risks and regretting the failure, Twitter did not comment on cases involving private accounts, which are closed to non-followers. Some users with “closed accounts” report that their tweets, in theory only available to approved followers, are appearing to people who don’t follow them.
Around the same time the Wheel bug appeared, other users reported that the “For You” section showed tweets from muted or blocked accounts. In this case, the social network also did not comment.