How To Fix GPSC129 - Only one Calc Type &1 or &2 could be assigned to Product &3 in period &4

SAP Error Message - Details

• Message type: E = Error

• Message class: GPSC - PSC Application

• Message number: 129

• Message text: Only one Calc Type &1 or &2 could be assigned to Product &3 in period &4

What causes this issue?

You are trying to enter two Calculation Types to a product where only
one is allowed in a given period

System Response

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

How to fix this error?

Please enter only one Calculation Type

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message GPSC129 - Only one Calc Type &1 or &2 could be assigned to Product &3 in period &4 ?

  The SAP error message GPSC129 indicates that there is a conflict in the assignment of calculation types for a specific product within a given period. This typically occurs in the context of SAP Advanced Planning and Optimization (APO) or SAP Integrated Business Planning (IBP), where multiple calculation types (like forecast, actuals, etc.) are being assigned to a product, but the system allows only one of the specified calculation types for that product in the defined period.
  Cause:
  
  Multiple Calculation Types: The error arises when there are attempts to assign more than one calculation type (e.g., forecast and actual) to the same product for the same time period.
  Configuration Issues: There may be configuration settings in the system that restrict the assignment of multiple calculation types to a single product.
  Data Entry Errors: Incorrect data entry or duplication in the planning data can lead to this error.
  
  Solution:
  
  Review Calculation Types: Check the calculation types assigned to the product for the specified period. Ensure that only one of the calculation types (either &1 or &2) is assigned.
  Adjust Planning Data: If multiple entries exist, you may need to delete or adjust the conflicting entries to ensure compliance with the system's restrictions.
  Configuration Check: Review the configuration settings in the system to understand why the restriction is in place. If necessary, consult with your SAP Basis or configuration team to modify the settings if business requirements allow for multiple calculation types.
  Data Consistency: Ensure that the data being uploaded or processed is consistent and does not contain duplicates or conflicting entries.
  
  Related Information:
  
  Transaction Codes: You may need to use transaction codes like /SAPAPO/SDP94 (for demand planning) or /SAPAPO/MC90 (for planning book) to review and adjust the planning data.
  Documentation: Refer to SAP documentation or help files related to planning and forecasting to understand the implications of calculation types and their assignments.
  Support: If the issue persists, consider reaching out to SAP support or your internal SAP team for further assistance.
  
  By following these steps, you should be able to resolve the GPSC129 error and ensure that your product's planning data is correctly configured.