order QTY broke into 2 amount after release

Dears,

we created an order that has item with quantity 6.25, after release i found that 2 delivery_Id created  for this line ,one`s quantity is 6 with "backorder" status, another one with quantity 0.25 and  "Released to Warehouse" status and its next step is "transfer move order". i should mention that in on-hand availibility we have 20000 (primary UOM) from this item and in inventory  in "move order transfer" i found nothing for this order number.

even i can not cancell the order line, i encounter error fail while cancelling.