Message type: E = Error
Message class:  BON_ENH_MESS - Message Class Extended Rebate 
Message number: 021
Message text: Enter the field name for the unit of measure
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
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The SAP error message BON_ENH_MESS021 typically indicates that a required field for the unit of measure (UoM) has not been filled in during a transaction or data entry process. This error often occurs in contexts where the system expects a specific unit of measure to be provided, such as in inventory management, sales orders, or material master data.
Cause: Missing Input: The most common cause is that the user has not entered a value in the field designated for the unit of measure.
Configuration Issues: There may be configuration settings in the SAP system that require certain fields to be filled out, and if they are not, the system will throw this error. Data Entry Errors: Users may inadvertently skip the field or enter an invalid value that the system does not recognize as a valid unit of measure.
Solution: Enter the Unit of Measure: The immediate solution is to locate the field for the unit
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