This article explains how to ban someone from your Facebook page. Once a person has been banned, they will no longer be able to comment, send messages or indicate that they like your page.
Steps
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Step 1. Visit https://www.facebook.com using a browser
To ban someone from a Facebook page, you'll need to use a browser (like Chrome or Safari) on a computer.
If you are not logged in to Facebook yet, enter your e-mail address and password in the fields indicated, then click on Log in.
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Step 2. Log in to your Facebook page
You will see all of your pages in the upper right corner of the screen, in a box called "Your Pages". If you don't see the one you want to open, use the arrows in the box to scroll through the pages until you find the one you are interested in.
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Step 3. Click on Settings
This option is located in the upper right corner of the page.
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Step 4. Click on People and other pages
This option is located in the column titled "General" on the left side of the screen.
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Step 5. Find the person you want to ban
Start typing their name in the search box in the upper right corner of the user list, then select the person in question from the search results.
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Step 6. Check the box next to the user's name
The box is to the left of the user's name. You can add the check mark by clicking on the box only once.
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Step 7. Click on the gear symbol
It is located to the right of the search box, just above the user list.
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Step 8. Select Lock to Page
A dialog box will appear.
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Step 9. Click Confirm
This user will be prevented from leaving comments, using the "Like" button and posting messages on your page.