Blank values Mail Chimp Community builder

Dear all,
I'm working on Joomla 3.6.4, Community Builder 2.0.15 and Joomlamailer (the last).
Everything works fine, my user registers on my site, every detail is stored, after admin confirmation and it's automatically synced with mail chimp, but there is only the email.

I have:
- name (std CB)
- surname (std CB)
- email (std CB)
- checkbox with few choices (same in Mailchimp)
- checkbox cb_newsletter

Please is there something that I miss?

thanks in advance for your kind support

Best regards
Alberto

Hi, I am also trying to resolve an issue but I can't get the fields into Mailchimp. Are you using the 'firstname' and 'lastname' fields in CB?