Message type: E = Error
Message class:  FI_E - Message Class for FM English Developers 
Message number: 228
Message text: Improper invoice: return date is mandatory
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The SAP error message FI_E228 "Improper invoice: return date is mandatory" typically occurs in the context of invoice processing, particularly when dealing with credit memos or returns. This error indicates that the system requires a return date to be specified for the invoice or credit memo being processed, but it has not been provided.
Cause: Missing Return Date: The primary cause of this error is that the return date field is not filled in the invoice or credit memo document. Configuration Settings: There may be specific configuration settings in the SAP system that mandate the entry of a return date for certain types of transactions. Document Type: The document type being used may have specific requirements that necessitate a return date.
Solution: To resolve the FI_E228 error, you can take the following steps: Enter Return Date: When creating or editing the invoice or credit memo, ensure that the return date field is filled in. This is typically found
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