Message type: E = Error
Message class:  MDG_BS_CUST_BOLUI - MDG: messages for Cusomer UI related issues 
Message number: 026
Message text: All sales areas have already been created for current ERP customer
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The SAP error message MDG_BS_CUST_BOLUI026 indicates that all sales areas have already been created for the current ERP customer. This typically occurs in the context of Master Data Governance (MDG) for Customer data, where the system is trying to create or update a customer record but finds that the sales area configuration is already complete.
Cause: Existing Sales Area: The customer record you are trying to create or modify already has all the necessary sales area data defined in the ERP system. Data Duplication: There may be an attempt to create a customer with sales area data that already exists, leading to this error.
Configuration Issues: There might be a misunderstanding in the configuration of sales areas or the way the data is being processed in the MDG workflow.
Solution: Check Existing Sales Areas: Review the existing sales area assignments for the customer in the ERP system. You can do this by navigating to the customer
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