2898388 - "Supplier" or "Customer" extension migration object raises error CVI_EI 11 or 41 or R11148 during data migration

When migrating data with the S/4HANA Migration Cockpit (transaction LTMC) or the Fiori app Migrate Your Data using migration object "Customer - extend existing record by new org levels" or "Supplier - extend existing record by new org levels, one of the following errors is raised:

Customer number does not agree with the assigned number
Message no. CVI_EI011

Vendor number does not agree with the assigned number
Message no. CVI_EI041

No business partner found
Message no. R11148

Even though the business partner / customer / supplier number exists in the system after checking in transaction BP.

• SAP S/4HANA​
• Transaction "LTMC"​
• Transferring Data Using Files​
• Transferring Data Using Staging Tables​
• "Migrate Your Data – Migration Cockpit" app​
• Migrate Data Using Staging Tables

R11148, R11 148, CVI_EI011, CVI_EI 011, CVI_EI041, CVI_EI0 41, extension, LTMC, Business Partner, supplier, vendor, customer, migration cockpit, Customer / Supplier extend existing record by new org levels, CVI_EI 041 , KBA , CA-GTF-MIG , SAP S/4HANA Data Migration Cockpit Content , LO-MD-BP , Business Partners , Problem