can't create OBD for Stock transfer order

HI gurus ,

I created an allocation table with the type 0001 standard allocation ,item category C ,and saved it .

Then I created the follow-on doc ,a PO generated for DC to vendor ,and I have done the inbound delivery for this PO of DC .

After that ,I create the follow-on doc by allocation talbe , several STOs generated, from DC to stores , with which I want to create Outbound delivery by VL10B ,but I got nothing at all ,not even any error message .

BTW, I have make sure the initial selection screen of the VL10B transaction is satisfied.

any suggestion?