Message type: E = Error
Message class:  /SAPAPO/PUIA_MESS -  
Message number: 121
Message text: User &1 is not assigned to planner of location product &2 &3
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The SAP error message /SAPAPO/PUIA_MESS121 indicates that a user is not assigned as a planner for a specific location product in the SAP Advanced Planning and Optimization (APO) module. This error typically arises when a user attempts to perform actions related to planning or managing a location product for which they do not have the necessary authorizations.
Cause: User Assignment: The user attempting to access or modify the location product is not assigned as a planner for that specific product in the system. Authorization Issues: The user may not have the required roles or authorizations to perform actions on the specified location product.
Configuration Issues: There may be a misconfiguration in the planning area or the assignment of planners to location products.
Solution: To resolve this error, you can take the following steps: Check User Assignment: Go to the transaction code /SAPAPO/LOC (Location Product Master) or use the relevant transaction to check the planner assignment for the location
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