To remove an additional FTP account, perform the following steps:
1 - 1 - Logged in to Plesk, https://your domain name:8443.
2 - Go to Websites & Domains.
3 - Click FTP Access.
4 - Select the checkbox corresponding to the FTP account you want to remove and click Remove. Note that the main FTP account of a subscription cannot be removed.
5 - Confirm removal and click OK.