I'm setting up a single Welcome letter for people who have recently signed up for a newsletter on my site. It has a personalized subject line with first name. There is just one automatic letter, not a series of automated responses. I have a basic account - and what I've read is that this feature is offered on this plan. But in other areas of the CC site it looks like I need to upgrade. Any advice why this auto-response would not be working? Could it be the personalization that is not included in my plan and is therefore blocking any response? ... View more