For some reason, I'm not getting an error number on sync. (However, I am getting an error/failed sync.)
Successfully syncronized 0 MailChimp users. 3 failed. Failure Details: (User ID: 1, Error: ), (User ID: 2, Error: ), (User ID: 3, Error: ), If needed, you can look up error codes here.
I tried setting a new API key, installed and uninstalled the plugin. In MailChimp, the API calls are showing a failure "listInterestGroupings" and "listMergeVars". "lists" are ok.
Does anyone know how to fix this?