11i - AX - Why Customer/Supplier Merge is erring out?

From AX User Guide,

The Global Accounting Engine does not support the following actions during a Customer or Supplier Merge because they violate reconciliation principles ensured by Global Accounting Engine reports:

• Deleting a customer after a merge.
• Creating accounting entries after a multiple merge.
• Merging unsuccessfully, such as a merge in Payables where only some of the invoices have been merged.
• Merging suppliers, when the new supplier site code already exists in another organization that has the same set of books ID.

Even though the 'delete after merge' checkbox is unchecked, Customer Merge may still fail for following reasons. These are not related to delete duplicate flag's functionality in any way.

• GL/subledger Period is closed (Open GL periods for merge date).
• No balance details found for SOB and application (Run Standalone Balance Calculation).
• Untranslated events exist for SOB and application (Submit AX posting Manager / Post Transactions).