I ran a fullcontact campaign on existing leads but they weren't updated I got response code "1000". asked FC support and they said it's a marketo thing (FullContact works fine when new leads are created though) any ideas?
You can't call a webhook from a batch campaign. You can either call from a trigger campaign or as part of a flow. Supposedly, Marketo is going to provide a more descriptive description at some point in the future.
Here is a link to another thread: https://community.marketo.com/MarketoDiscussionDetail?id=90650000000PqDnAAK