Special procurement type for costing will be reset

What causes this issue?

You are trying to enter the special procurement type for phantom
assemblies in the Costing view, which you want to override the special
procurement type in the MRP view when the material is costed. This
entry is not possible in the Costing view.

System Response

The system resets (that is, cancels) the special procurement type for
phantom assemblies in the Costing view.

How to fix this error?

Check your entry.
If you want to cost the material as a phantom assembly, enter
special procurement type <LB>50</> in the MRP view and leave the
special procurement type blank in the Costing view.
If you then cost the material, the system determines the planned costs
of the BOM components in the phantom assembly.

Error message extract from SAP system. Copyright SAP SE.