Kanban stock transfer with reservation

Dear Gurus,

I set on the customizing the standard movement type 251, to the replenishment strategy "stock transfer with reservation", but it seems that the system is creating reservations numbers with out internal order number, even if is set that an internal order number is necessary to input.

Checked all customizing settings with no success, is there something else that must be done, to avoid creating reservations number on Kanban process without internal order?

Regards

Oliver F