Do you mean the login info for DH panel?
The login info for DH panel is different from FTP login. You can check your FTP username and password via DH panel --> Users --> Manage Users. In DH, you can assign a same/different FTP user to each domain.
You can change the FTP user of a domain via DH panel --> Domains --> Manage Domains --> Web Hosting --> Edit. Here you see the FTP user of the domains.
Warning: if you change FTP user, the path to the domain will be changed. You will need to move the files to the new directory.
Do you mean you can't get into WebFTP? You may want to try to have a new password for the FTP user and try again. Make sure it is your FTP username and password.
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