Vendor Invoice - Outgoing Payment -How to apply cash discount automatically

Hi Folks,

My Vendor is 400000 - whose payment terms is : 0002

I posted a vendor invoice using FB60 :

where i checked the payment terms is 0002 3% Cash Discount within 14 days

2% Cash discount within 30 days

Net within 45 dats

Default for Baseline date : Posting Date.

My Document Date and Posting date are both same: Invoice Document and posting date : 07/31/2008

I tried to make a payment using F-53, where the Cash Discount is not applying automatically. It is asking me to manually enter the cah discount @ 3%.

What should i do to make cash discount apply automatically.

Thanks and Help will be surely rewarded.

Matthew