Reconciliation 
You may have to run a reconciliation report if the SAP Business Partner has already been used in the system in which the conversion is taking place. The converted SAP Business Partners (in other words, those that were generated from Treasury Business Partners) are reconciled with the existing SAP Business Partners. You may have to run a report to delete them.
You have generated the Customizing for the SAP Business Partner and the conversion Customizing between the Treasury and the SAP Business Partner, and have converted the Treasury Business Partner to the SAP Business Partner. SAP Business Partners already existed in your system.
The reconciliation is carried out in three steps:
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1. Run the report RFTBUP03 to determine duplicates (business partners that exist twice in the system) and mark these for reconciliation (Existing and Migrated Partners (RFTBUP03)).
2. Run the report RFTBUP03_2 to reconcile the selected business partners (Reconciliation Report: Selected Partners (RFTBUP03_2)).
The system processes the list of duplicated SAP Business Partners generated by report RFTBUP03. It compares the partners with each other and copies the data from the migrated SAP Business Partners to the SAP Business Partners that already exist.
3. If necessary, delete the migrated duplicates by running the report (Deletion Report for Reconciled (Duplicated) SAP BP (RFTBUD03)).

If you have to run a reconciliation report, execute this report before you run the conversion report RFTBUP06 Convert Notes.
You have determined and selected the duplicate business partners. The data for the migrated SAP Business Partners was transferred to the already existing SAP Business Partners. You may also have deleted the migrated duplicate business partners.