Message type: E = Error
Message class:  ICA02 - ICA Matching Engine Message Class 
Message number: 055
Message text: Value of mandatory field &1 inconsistent between header and line items.
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The SAP error message ICA02055 indicates that there is an inconsistency between the values of a mandatory field in the header and the line items of a document. This typically occurs in scenarios where certain fields must have the same value across both the header and the line items, such as in sales orders, purchase orders, or invoices.
Cause: The inconsistency can arise due to several reasons: Manual Entry Errors: A user may have entered different values for the mandatory field in the header and line items. Data Migration Issues: If data was migrated from another system, inconsistencies may have been introduced.
Configuration Issues: The system may be configured in a way that requires certain fields to match, but the data does not comply with this requirement. User Exits or BAdIs: Custom code or enhancements may be affecting the values being set in the header or line items.
Solution: To resolve the error, follow these steps: Identify the Field:
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