ACME.ERROR Unknown user

[omBratteng]

Running the code

sudo bin/acme issue \
    --server acme-v01.api.letsencrypt.org/directory \
    --domains bratteng.xyz,www.bratteng.xyz \
    --path /home/nginx/bratteng.xyz/ssl

And I'm getting the error

[2016-01-17 08:33:40] ACME.INFO: Checked DNS records, all fine.
[2016-01-17 08:33:40] ACME.INFO: Found account keys.
[2016-01-17 08:33:40] ACME.DEBUG: Generating payload...
[2016-01-17 08:33:40] ACME.ERROR: Kelunik\Acme\AcmeException: Unknown user: www-data in /root/acme-client/src/Commands/Issue.php:88

Running latest version of nginx and php

[kelunik]

You can use the --user argument to specify the user running your server.