Failed Authorized Procedure: Error parsing key authorization file

This is the error I get when running the client with this command

./letsencrypt-auto certonly --config /etc/letsencrypt/cli.ini -d mydomainname.com -d www.mydomainname.com

Error:
Failed authorization procedure. www.mydomainname.com (http-01): unauthorized :: The client lacks sufficient authorization :: Error parsing key authorization file: Invalid key authorization: 156 parts, mydomainname.com (http-01): unauthorized :: The client lacks sufficient authorization :: Error parsing key authorization file: Invalid key authorization: 156 parts

My config file looks like this

authenticator = webroot
webroot-path = /var/www/
server = https://acme-v01.api.letsencrypt.org/directory
renew-by-default
agree-dev-preview
agree-tos

What am I doing wrong?

This command seems to work:

./letsencrypt-auto certonly -a webroot --webroot-path /var/www/mydomainname/ -d mydomainname.com -d www.mydomainname.com --server https://acme-v01.api.letsencrypt.org/directory --agree-dev-preview