ALTERNATIVE WAY for Facebook Profile Lock

If locking your profile isn't available to you, you can control your privacy in other ways through your privacy settings:

✓Use Privacy Checkup.
✓Choose who you share posts, photos and other information with.
✓Edit basic info and choose who can see it.
✓Change your story privacy settings.
✓Turn on Profile Review.
✓Turn on tag review
✓Turn on Profile Picture Guard.
✓Control Who Can Friend And Follow You.
✓Control who can look you up using your email or mobile phone number.

https://www.facebook.com/help/196419427651178

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