Message type: E = Error
Message class:  ICCMP_BTX - Interaction Center - Business Transaction Messages 
Message number: 018
Message text: Contact person &1 is not mapped to ERP business partner
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The SAP error message ICCMP_BTX018 indicates that a contact person (represented by &1) is not mapped to an ERP business partner. This typically occurs in scenarios where there is a need to link a contact person in a system (like SAP CRM or SAP S/4HANA) to a business partner in the ERP system, and the mapping has not been established or is incorrect.
Cause: Missing Mapping: The contact person exists in the system but has not been assigned to a corresponding business partner in the ERP system. Incorrect Configuration: The configuration settings for business partner integration may not be set up correctly. Data Inconsistency: There may be inconsistencies in the data between the systems, such as different identifiers or missing entries. Transport Issues: If the business partner data was transported from one system to another, the mapping might not have been included.
Solution: Check Business Partner Mapping: Go to the transaction code BP (Business Partner) in the ERP
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