However, he may have simply changed his security settings to prevent anyone but friends from searching for him. Try logging out of Facebook or toggling to your business account (click the arrow in the upper right corner and select “Log In As”). See: How Can I Log Out On Facebook App
Try searching for the person again. If the person is not visible in a public search or from your business account, you may have been blocked. If the person is visible in a public search, but not visible in a search from your personal account, you’ve been blocked.
Mutual Friend ListMutual friends can be a good indicator to see if you have been blocked. Navigate to a profile of someone who was a mutual friend with the person you suspect has blocked you. A list of some of her current friends is on their profile page.
Click the “See All” link at the top of the list. A search field appears at the top of the page, which you can use to type the person’s name. If the person’s profile appears, you have not been blocked. If it doesn’t appear, you may have been blocked.
While few people have their friends listed publicly if you can find such a person, try logging out of Facebook and looking at their list of friends. If the person is visible there, but not when you were logged in, you have been blocked.
FB Block in Wall PostsIf you can remember any posts the person has placed on your profile, business page or a mutual friend’s page in the past, finding those posts now can indicate whether you’ve been blocked. If you have been blocked, the wall posts will still be visible, however, his profile picture will be replaced with a question mark.
Additionally, the person’s name will be in black text and will no longer be a clickable link to his profile page.
Other MethodsSo far, all of the above methods are ways you can determine if you have been blocked without drawing attention to yourself. To determine without a doubt if you have not been blocked, try sending a Facebook message to the person. If you receive a reply, you have not been blocked. You can also ask mutual friends if they have seen the person on Facebook recently. See: My Blocked List on Messenger – How to Unblock People on Facebook Messenger
If no one has, the person may have terminated her account or may have been suspended from Facebook. Lastly, you can ask your friends, or the person directly, whether you have been blocked.