How To Fix CN870 - Choose another key for alternative; this one already exists

CN870 - Overview

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 870

• Message text: Choose another key for alternative; this one already exists

What causes this issue?

The alternative you have entered for the standard network already
exists. Either the standard network is:
marked for deletion or
in a validity area, that does not agree with the key date.

System Response

INCLUDE 'NA_ALLG_NOVERARBEITUNG' OBJECT DOKU ID TX

How to fix this error?

Enter a different key for the alternative.

Error message extract from SAP system. Copyright SAP SE.

CN870 - Details

• The SAP error message CN870 ("Choose another key for alternative; this one already exists") typically occurs in the context of project management or when working with alternative items in SAP. This error indicates that you are trying to create or assign an alternative key (such as a project number, WBS element, or other identifiers) that already exists in the system.
  
  Cause:
  
  Duplicate Key: The primary cause of this error is that the key you are trying to use has already been assigned to another object in the system.
  Data Entry Error: It may also occur due to a simple data entry mistake where the same key is inadvertently entered multiple times.
  System Configuration: In some cases, the system configuration may not allow for certain keys to be reused or may have restrictions on key formats.
  
  
  Solution:
  
  Check Existing Keys: Before creating a new alternative key, check the existing keys in the system to ensure that the