With the MailChimp API, to add a member to a list with a specific interest group, you need both that list\'s ID and the interest group\'s ID.
To get both those IDs, you
You can use either interest group id or its name for this(Hope you are using MaiChimp API v3). You can find it the MailChimp interface itself.
You need to use name instead of id as the parameters.
name
id
Please let me know if have any issue with using it. :)