FTP not working on a specific WordPress site but working on others (and Filezilla) [closed]

It looks like the FileZilla username and password are your droplet’s root and root password. You may just need to update them.

https://docs.digitalocean.com/support/how-do-i-reset-my-droplets-root-password/,
https://www.digitalocean.com/community/questions/ftp-access-to-droplet-i-dont-want-ssh