How To Fix /SCF/CL_MDL_MESSAGES020 - Level &1: Parent &2 with child &3 not allowed

/SCF/CL_MDL_MESSAGES020 - Overview

• Message type: E = Error

• Message class: /SCF/CL_MDL_MESSAGES -

• Message number: 020

• Message text: Level &1: Parent &2 with child &3 not allowed

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

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/SCF/CL_MDL_MESSAGES020 - Details

• The SAP error message /SCF/CL_MDL_MESSAGES020 Level &1: Parent &2 with child &3 not allowed typically occurs in the context of SAP's Supply Chain Management (SCM) or Advanced Planning and Optimization (APO) modules. This error indicates that there is a hierarchical relationship issue between a parent and child object in a model or planning scenario.
  
  Cause:
  
  
  Hierarchical Structure Violation: The error suggests that the relationship defined between the parent (object &2) and the child (object &3) is not allowed based on the configuration or business rules set in the system. This could be due to:
  
  Incorrect configuration of the parent-child relationship in the master data.
  The child object is not valid for the specified parent object.
  The parent-child relationship is not defined correctly in the planning model.
  
  
  
  Data Integrity Issues: There may be inconsistencies in the data that prevent the system from recognizing the relationship as valid.
  
  
  Business Rules: Certain business rules may restrict specific parent-child combinations based