Change delivery qty after cancelling partial goods receipt inbound delivery

Dear all,

I'm trying to set up a goods receipt from vendor flow in a WM-HU environment, using partial goods receipt, but unfortunately I'm experiencing an issue.

The flow is as follows:

Create purchase order (ME21N)
Create inbound delivery (VL31N)
- Create batch + pack goods into HUs
- Create & confirm putaway TO per HU (this triggers the post goods receipt for the specific HU, the customizing allows the partial goods receipt (see attachment1))

Example of the problem:

purchase order for 100PC
packed into 2 HUs of 50PC each
after confirming the putaway TOs (and thus posting the goods receipt, see attachment2) the warehouse operator notices that one of the HUs only contains 40PC
the delivery quantity therefore should be only 90PC instead of 100PC; and the HU qty of one of the HUs should be 40PC instead of 50PC
via VL09 I can select the material document I want to cancel (see attachment3).
the total goods movement status for the inbound delivery is now again 'B' (see attachment4).
I now unpack 10PC to become a HU of 40PC instead of 50PC (see attachment5).
until now everything goes as planned, but when I want to reduce the delivery qty from 100 PC to 90 PC (50 + 50 40), I get an error message (see attachment6).

Is there a way to get this flow working? I found SAP note 796053 - Quantity change after partial goods receipt, but that's only for older SAP systems.

All help would be much appreciated! Thanks in advance for any input!

Kind regards,

Niels Loncke

Print screens:

Attachment1