Message type: E = Error
Message class:  CRM_IST_SO_MSG - Messages for Package CRM_IST_SO 
Message number: 031
Message text: Value &1 is not allowed in field &2
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The SAP error message CRM_IST_SO_MSG031, which states "Value &1 is not allowed in field &2," typically occurs in the context of SAP Customer Relationship Management (CRM) when a user attempts to enter a value in a field that is not valid according to the system's configuration or business rules.
Cause: Invalid Value: The value entered in the specified field does not meet the criteria defined in the system. This could be due to: The value not being part of the allowed values for that field. The value being outside of a defined range. The value being incompatible with other fields or settings in the document. Field Configuration: The field may have specific settings or restrictions that prevent certain values from being accepted. This could be due to: Custom validations implemented in the system. Missing or incorrect configuration in the field settings. Data Consistency: The entered value may violate data consistency rules, such as dependencies between fields or business logic
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