Question about Advance Parole

For the class of admission on application for travel document, I put "Deferred action for childhood arrivals." Do i need to put my case number as well? I lost my receipt and I don't remember what the number is.

Also, what do I need to send with the form?

You don't need to put the case number. You will be sending the necessary documents that support your need for advance parole and your DACA approval letter

I misplaced my approval letter, is there anything I can do?

Put copy of the EAD. They have all your stuff.