Problem while generating FA (CONTRL MSG)


I need to generate a CONTRL Message when i get an ORDERS msg into my TN.I have already set the fields of TPA like

autoGenerateFA : on
FAReconciliation :true

But still it’s not generating the FA and in the transaction analysis it showing that that orders msg is received and in the attributes column of Document Details the EDI Acknolwdgement filed is DISABLED.