How To Fix CN455 - Milestone belongs to a billing plan - cannot change assignments

SAP Error Message - Details

• Message type: E = Error

• Message class: CN - Meldungen für Netzpläne

• Message number: 455

• Message text: Milestone belongs to a billing plan - cannot change assignments

What causes this issue?

You cannot change the assignment of the milestone to an activity,
because the milestone is assigned to a billing plan.

System Response

INCLUDE NA_ALLG_NOVERARBEITUNG OBJECT DOKU ID TX

How to fix this error?

If you want to assign the milestone to another activity, delete the
date from the billing plan first.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message CN455 - Milestone belongs to a billing plan - cannot change assignments ?

  The SAP error message CN455 indicates that you are trying to change the assignment of a milestone that is part of a billing plan. This error typically occurs in the context of project management and billing processes within SAP, particularly when dealing with milestones in project systems (PS) or sales and distribution (SD).
  Cause:
  The error arises because the milestone you are attempting to modify is linked to a billing plan. In SAP, billing plans are used to define how and when billing occurs for a project or service. When a milestone is associated with a billing plan, it is locked for changes to ensure the integrity of the billing process. This prevents any modifications that could disrupt the billing cycle or the financial reporting associated with the project.
  Solution:
  To resolve the CN455 error, you can consider the following steps:
  
  
  Check the Billing Plan: Review the billing plan associated with the milestone. Ensure that any necessary changes to the billing plan are made before attempting to modify the milestone.
  
  
  Remove the Milestone from the Billing Plan: If you need to change the milestone, you may need to first remove it from the billing plan. This can typically be done in the billing plan configuration or by using transaction codes related to billing plans.
  
  
  Consult with Stakeholders: If the milestone is critical to the billing process, consult with project managers or financial stakeholders to determine the best course of action. They may provide insights on whether the milestone can be adjusted or if a new milestone should be created.
  
  
  Create a New Milestone: If changing the existing milestone is not feasible, consider creating a new milestone that meets your requirements without affecting the billing plan.
  
  
  Check Authorizations: Ensure that you have the necessary authorizations to make changes to the billing plan and milestones. Lack of proper permissions can also lead to errors.
  
  
  SAP Notes and Documentation: Check for any relevant SAP Notes or documentation that may provide additional context or solutions for this specific error message.
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as CJ20N (Project Builder), CJ02 (Change Project), or VF01 (Create Billing Document) that may be involved in managing milestones and billing plans.
  SAP Help Portal: Utilize the SAP Help Portal for detailed documentation on project management and billing processes.
  User Forums and Communities: Engage with SAP user communities or forums where similar issues may have been discussed, providing insights or solutions from other users' experiences.
  
  By following these steps, you should be able to address the CN455 error and proceed with your project management tasks effectively.