How To Fix VL424 - & serial numbers are already maintained. Quantity cannot be changed

SAP Error Message - Details

• Message type: E = Error

• Message class: VL -

• Message number: 424

• Message text: & serial numbers are already maintained. Quantity cannot be changed

What causes this issue?

The delivery quantity cannot be changed to a number lower than the
serial numbers you have already assigned.

System Response

The system rejects the change of quantity.

How to fix this error?

First delete the serial numbers that were not delivered, thereby
adjusting the number of serial numbers to match the desired delivery
quantity. Then you can reduce the delivery quantity.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message VL424 - & serial numbers are already maintained. Quantity cannot be changed ?

  The SAP error message VL424 ("Serial numbers are already maintained. Quantity cannot be changed") typically occurs in the context of handling serial numbers in inventory management or sales and distribution processes. This error indicates that the system has detected that serial numbers have already been assigned to a specific quantity of items, and therefore, you cannot change the quantity of that item in the document (like a delivery or sales order).
  Cause:
  
  Serial Number Assignment: The error arises when you attempt to change the quantity of a material that has already been assigned serial numbers. In SAP, once serial numbers are assigned to a specific quantity, that quantity is locked for changes.
  Document Type Restrictions: Certain document types may have restrictions on changing quantities once serial numbers are assigned.
  Incomplete Processing: If the document is in a state where it cannot be modified (e.g., already processed or completed), you may encounter this error.
  
  Solution:
  
  Check Serial Number Assignment: Review the serial numbers that have been assigned to the material. You can do this by navigating to the relevant transaction (e.g., using transaction code IQ03 for displaying serial numbers).
  Adjust Quantity: If you need to change the quantity, you may need to first remove the serial number assignment. This can be done by reversing the document or adjusting the stock in a way that allows you to reassign serial numbers.
  Use the Correct Document Type: Ensure that you are using the correct document type that allows for quantity changes. If the document is already processed, you may need to create a new document.
  Consult with SAP Support: If you are unable to resolve the issue, consider reaching out to your SAP support team or consulting the SAP Help Portal for more specific guidance related to your system configuration.
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as VL01N (Create Outbound Delivery), VL02N (Change Outbound Delivery), and IQ03 (Display Serial Number).
  Documentation: Review SAP documentation related to serial number management and inventory processes to understand the implications of serial number assignments.
  User Roles and Permissions: Ensure that you have the necessary permissions to make changes to the document in question.
  
  By following these steps, you should be able to address the VL424 error and manage your serial number assignments effectively.