batch split in outbound delivery

Hi experts,

Pls advise how to process batch split for the case below? Any configuration?

Case: material XX against storage location C in one delivery - qty 1900 kg (including batch A - 1100 kg, & batch B - 800 kg)

Issue: During batch split in the delivery, the system pops up " Only 100 KG of material XX batch A available Message no. VL150". Batch B can be confirmed completely.

If reducing delivery qty to 1100 kg against batch A only, the system does not pop up the message above. It can be confirmed completely.

More info: MMBE - unrestricted stock 3044 kg against all the storage locations

- unrestricted stock 1900 kg against storage location C (including batch A - 1100 kg, & batch B - 800 kg)

- schd. for delivery 3900 kg including 1900 kg against C

Background: Availability check is off when creating delivery. Thus the schd. for delivery qty exceeds the unrestricted stock. IM is applied. There's another open delivery (2000 kg - not picked, no batch split) which is not specified storage location.

My comments: There are only two deliveries against the same material. One is 1900 kg, the other is 2000 kg. Suppose 1900 kg can be batch split as 2000 kg does not consume stock. U know, availability check is off when creating delivery.