Delayed automatic form entry response

We wanted to create automatic delayed response to a form entry. It would send email back to whatever email was entered into form field 72 hours after the form has been filled. The response would say something like: "Your request has been approved". 

We wanted auto data stamp column to generate that response but automation is not recognizing auto data stamp column. 

I have not been able to find a function under automation that would allow for something like that. Am I missing something ?

Thanks