Message type: E = Error
Message class:  FI - TR-FM Funds Management 
Message number: 644
Message text: Company code &: assigned currency key does not exist
Currency key &V3& does not exist in FM area &V2&, which is assigned to
company code &V1&.
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.
The SAP error message FI644 indicates that there is an issue with the currency key assigned to a company code in the Financial Accounting (FI) module. Specifically, the error message states that the currency key assigned to the company code does not exist in the system.
Cause: Missing Currency Key: The currency key assigned to the company code is not defined in the system. This can happen if the currency was not set up properly during the configuration of the company code. Incorrect Configuration: The company code may have been configured with an incorrect or misspelled currency key. Transport Issues: If the configuration was transported from another system (e.g., from a development to a production environment), the currency key may not have been included in the transport request. Data Migration Issues: If data was migrated from another system, the currency key may not have been correctly mapped or defined.
Solution: Check Currency Configuration: Go to the transaction code
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