3438270 - Error message MH139 when creating generic material

During generic material creation on plant you receive MH139 error: 

Short Text
You can maintain only reference plants for generic materials

Diagnosis
The data for a generic material and for a special plant that is not a reference plant can be used neither in maintenance nor by operational functions. For this reason, it is not possible to maintain such data.

The reference data for variants and special plants that are not reference plants is at the level of the variant itself and of the respective reference plants.

SAP ERP

SAP S/4HANA

MH139, MH 139, WSS1, MARC, MM41, generic material, generic article, plant, site, store , KBA , LO-RFM-MD-ART , Article , IS-R-BD-ART , Articles , LO-MD-PL , Plant Master , LO-RFM-MD-SIT , Site , Problem