Un able to integrate Zoho CRM and MailChimp

Un able to integrate Zoho CRM and MailChimp

Dear Support, I am trying in vain to integrate ZCRM with Mailchimp. MailChimp ask me to review my Username and password. I am a google apps user and my MailChimp account is Google Apps based. My Google apps account credentials are same with Zoho CRM credentials. Regards.