How To Fix 29123 - Sub-item number has already been assigned

29123 - Overview

• Message type: E = Error

• Message class: 29 - Bills of Material

• Message number: 123

• Message text: Sub-item number has already been assigned

What causes this issue?

You want to create a sub-item for an existing item.
The item number you entered has already been assigned.
Sub-items are uniquely identified within the item by the sub-item
number, so each sub-item number can only be assigned once.

How to fix this error?

Enter a sub-item number which has not yet been assigned.

Error message extract from SAP system. Copyright SAP SE.

29123 - Details

• The SAP error message 29123, which states "Sub-item number has already been assigned," typically occurs in the context of materials management or inventory management when dealing with sub-items in a bill of materials (BOM) or during the creation of purchase orders, production orders, or similar transactions.
  
  Cause:
  This error usually arises when:
  
  Duplicate Sub-item Assignment: You are trying to assign a sub-item number that has already been assigned to another item or entry in the system.
  Incorrect Data Entry: There may be a mistake in the data entry where the same sub-item number is being reused unintentionally.
  
  Configuration Issues: There might be issues in the configuration of the material master or BOM that allow for duplicate entries.
  
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Check Existing Assignments:
  
  Review the existing sub-item numbers in the relevant transaction (e.g., BOM, purchase order) to ensure that the sub-item number you are trying to assign is not already in