Can’t transfer backup files to FTP server, always prompts ‘Access Denied’?

I have a home server through ubuntu and I want to use it to store my backups of my laptop, I set it up as an vsftpd FTP server. I can use WinSCP to transfer other files, but when I try transferring the backup from the laptops external hardrive, it will only transfer the folder name and nothing else. When I use commands to do it, it prompts me with ‘Access denied’ and nothing more. Does anyone know any workarounds?