Facebook introduced the profile locking feature to give users more control over who can see their profile information. When a user locks their profile, it restricts access to their profile and timeline, making it harder for people to see their information if they're not friends or followers.
That being said, here are some general tips on how to view a locked Facebook profile: facebook locked profile viewer online link
Search Engines: Occasionally, older public versions of a profile might be cached on search engines like Google or Bing, though this rarely works for profiles that have been locked for a long time. Facebook allows users to control who can see
Facebook allows users to control who can see their profile information and posts through privacy settings. A locked profile, often a result of strict privacy settings, restricts the visibility of a user's profile and posts to only their confirmed friends or followers, depending on their settings. This move towards privacy is a response to growing concerns over online safety and data protection. facebook locked profile viewer online link