Message type: E = Error
Message class:  FKKBIX_BIP -  
Message number: 155
Message text: Billing plan &1 completed.
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The SAP error message FKKBIX_BIP155, which states "Billing plan &1 completed," typically occurs in the context of billing and invoicing processes within the SAP system. This error indicates that the billing plan associated with a specific contract or order has been completed, and therefore, no further billing actions can be performed on it.
Cause: Completed Billing Plan: The billing plan referenced in the error message has already been fully processed, meaning all billing cycles have been completed, and no further invoices can be generated. Incorrect Status: The status of the billing plan may not allow for additional billing actions, possibly due to prior completion or closure of the billing cycle.
Configuration Issues: There may be configuration settings in the billing plan that restrict further processing once a certain condition is met.
Solution: Check Billing Plan Status: Review the status of the billing plan in question. If it is indeed completed, you will need to determine if
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