Error: Action not possible for picking relevant items /SCWM/DELIVERY 183

[Vimala]

When creating direct outbound delivery with nested HUs, the system ends up with error /SCWM/DELIVERY 183. This error is captured in /SCWM/CL_IM_PRDO_ACTION_HU~CREATE_ITEM_FOR_HU in line 382 loop, where item relevance is validated for WM move. Since its relevant, the error message was displayed. I am not sure why the status relevant is an error here. Please advise if anyone have any experience or solution for creating direct outbound delivery with nested HU. 

[HakanHaslaman]

Looks the system is trying to create an item for a HU that it considers relevant, but it's encountering an issue because the HU is nested within another HU. Did you already check the HU structure in the system matches the actual HU structure?