Due to a bug in Twitter for Android, the app has exposed the private Tweets of an unknown number of users for over 4 years. The issue caused the app to make changes to the accounts of affected users, such as turning off the “Protect your Tweets” setting.
The bug was fixed earlier this week. Twitter has informed affected users about the issue and restored their settings.
Read more: Twitter Fixes Four Year Old Bug in Android App Exposing Private Tweets