The Acknowledgment date of a document must not predate the document date. Complete all three pages of Notice to Defend and Divorce Complaint using the detailed."Instruction for Forms" as a guide. 2. There must be a Social Security Number, if available, in the birth mother's and birth father's sections of the Acknowledgment of. Letter. 1. Executive Summary. Complete this form to request a new support case. We've created two easy-to-use templates to help you write your acknowledgment letter.