1. Log into your cPanel account.
2. In the "Files" section, click on "FTP Accounts" Icon.
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3. Under the "FTP Accounts" list, Click on "Delete" button.
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4. Click on the "Delete Account" button and your FTP Account will be removed.
Warning: Do not use the "Delete Account and Files" option. Otherwise the data inside your FTP User account will also be removed and will be unrecoverable until you restore it with a backup.