Default cost element in F-47

Hello Gurus,

When I make the down payment request or down payment while system showing the below error message ,here my doubt is suppose if I want to give the default cost element which gl account shall use and how the data flow in to the system

Note : I am making the payment reference of purchase order , while system automatically take the investment order number also

Error message

Maintain default cost element in controlling area XXXX

Message no. FI660

Diagnosis

CO down payment update is active in controlling area xxxx. You must therefore maintain a default cost element and a default revenue element for down payments.

Procedure

Maintain the default cost elements for down payments for controlling area xxxx in the Project System implementation guide.

Thansk & Regards

Sri