unable to connect to SFTP using Nginx One Click droplet

I’m trying to connect via sftp to a one-click LEMP droplet, but after creating a superuser and granting ownership of the web directory, sftp login still fails for both root and my newly created superuser.

Here’s what I’ve run to set up my user so far: adduser logan usermod -aG sudo logan rsync --archive --chown=logan:logan ~/.ssh /home/logan

As far as permissions and groups go, I’ve done the following (domain.com as placeholder for my actual domain)

sudo chown www-data:www-data /var/www/domain.com sudo chmod -R 775 /var/www/domain.com

I’ve been using the following docs: https://www.digitalocean.com/community/tutorials/initial-server-setup-with-ubuntu-18-04 https://www.digitalocean.com/community/tutorials/how-to-set-up-nginx-server-blocks-virtual-hosts-on-ubuntu-16-04 https://www.digitalocean.com/community/tutorials/how-to-secure-nginx-with-let-s-encrypt-on-ubuntu-18-04

Is there something else that needs to be done after starting the one-click droplet? I saw a help article that said I needed to change the root password first, but I’m using an SSH key for my root account (selected during droplet configuration).

Thanks in advance for any assistance.