SAP Message V1009 - Material &1 is managed as customer material &2 (please check)

Diagnosis
You have changed either the Customer material field or theMaterial field. The 'dependent' field was not redetermined.

System Response
The system determines the 'dependent' field only when there is no valuein the field. When you change the Customer material field, forinstance, the Material field is dependent. When you change theMaterial field, the Customer material field is dependent.

Procedure
In order for the system to automatically redetermine the 'dependent'field when you are changing something, you must delete the field'scontents.