ActiveCampaign Forum

Automation does not add contact to list

Hi guys,
I created a list and a form connection with caldera forms add-on for AC. If a new contact (who I do not have in any list) register with this form the contact will be added to the list. If an existing contact in my AC will register with this form he will not added to the list.
Does anybody know why?
Thx!!
Flo