Item not picked by FIFO rule

We have a scenario where in an Organization there are two types of item,

ITEM A: LOT Enabled and Shelf Life Enabled

ITEM B: Only LOT Enabled.

I want that for item A the picking rule must follow FEFO method, and for ITEM B it should follow FIFO method. I have defined both the rules and assigned it on the organization by rules workbench. But the application is only picking the item through FEFO not with FIFO.

Regards,

Yousuf Pishori