Do you know how to trouble shoot this error message?

I see this error message when attempting to log in as a new user. I have "membership" installed, synced with the mailchimp plugin. Do you know what I can do to fix this? Thanks

Warning: MailChimp listSubscribe() Error: 200 - Invalid MailChimp List ID: in /home1/larpoon/public_html/askloralee.com/wp-content/plugins/mailchimp-sync/mailchimp-sync.php on line 144

Warning: Cannot modify header information - headers already sent by (output started at /home1/larpoon/public_html/askloralee.com/wp-content/plugins/mailchimp-sync/mailchimp-sync.php:144) in /home1/larpoon/public_html/askloralee.com/wp-includes/pluggable.php on line 681

Warning: Cannot modify header information - headers already sent by (output started at /home1/larpoon/public_html/askloralee.com/wp-content/plugins/mailchimp-sync/mailchimp-sync.php:144) in /home1/larpoon/public_html/askloralee.com/wp-includes/pluggable.php on line 682

Warning: Cannot modify header information - headers already sent by (output started at /home1/larpoon/public_html/askloralee.com/wp-content/plugins/mailchimp-sync/mailchimp-sync.php:144) in /home1/larpoon/public_html/askloralee.com/wp-includes/pluggable.php on line 683

Warning: Cannot modify header information - headers already sent by (output started at /home1/larpoon/public_html/askloralee.com/wp-content/plugins/mailchimp-sync/mailchimp-sync.php:144) in /home1/larpoon/public_html/askloralee.com/wp-content/plugins/qa/core/edit.php on line 402

Warning: Cannot modify header information - headers already sent by (output started at /home1/larpoon/public_html/askloralee.com/wp-content/plugins/mailchimp-sync/mailchimp-sync.php:144) in /home1/larpoon/public_html/askloralee.com/wp-includes/pluggable.php on line 899