Still not working. I'm trying the same, looking for advanced custom field that I've added to my post. Here it is:
Best answer by Danvers
The Create Post action for WordPress doesn’t support custom fields, I’m sorry about that! We do have a feature request open for this and I’ve added you as an interested user. This lets the team know how many folks would like to see this addition and also means that we’ll send you an email when we have an update.