FasTrack process issue

Hi SRM experts,

We have activated FasTrack process in SRM 5.0 for all product categories

Category ID Souce System Sourcing
*          Blank         3 Sourcing carried out for items without assd source of supply

Then we are Creating a Header & Item Contract for a Product category-Office supplies in SRM 5.0 (i.e no Product maintained only product category maintained)

Contract released..

then

Creating a shopping cart for the same product catgeory (Office supplies) but Souce of supply not detected automatically..

Pls let me know what could be the reason for this issue

Point Checked:

1)Define Sourcing for Product Categories

Category ID    Souce System              Sourcing
*                      Blank                          3 Sourcing carried out for items without assd source of supply

2)Only one Local Contract exist for the product category

Thanks,

San..