Twitter seems to have removed the DM feature where anyone could send DMs to anyone.
Good move, imho.
Last month, Twitter quietly rolled out a new feature to give users the choice to receive private messages from any of their followers, but that option has now been removed.
A checkbox to opt in to the feature was previously found under the account settings, but it is no longer there. This means Twitter users are back to being unable to send a direct message to someone in their follower list if their chosen recipient isnít following them back.Twitter Removes The DMs From Any Follower Feature [thenextweb.com]