Will not display inputted date

The follwoing query will not display [forms]![process dd]![paydate] from the select part of the statment, even though it works fine in the where clause. It just show a blank field. Is there any way to do what I want. I just want to display the date the user inputted within the query. The below query is a bit funny as Sage wants are data in a very specific format.

Code:

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SELECT "SA" AS TT, Contacts.Sage, 1251 AS bank, billing.DeptNo,[InvoiceDate],[forms]![process dd]![paydate] AS Recdate, "DD" & sage AS recRef, "Payment on Account" AS Description, Format(Invoices.PayeeAmount,"£#,##0.00;(£#,##0.00) ") AS payeeam, "T9" AS vatcode, 0 AS Vatamount
FROM (Invoices INNER JOIN Contacts ON Invoices.Contactid = Contacts.ContactID) INNER JOIN billing ON Invoices.Contactid = billing.Contactid
WHERE (((DateDiff("d",[InvoiceDate],[forms]![process dd]![paydate]))>13) AND ((Invoices.Invoicetype)="Direct Debit") AND ((Invoices.SubmittedtoBacs)=False))
ORDER BY Invoices.moneypennyid;

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