How To Fix FINS_FI_MIG123 - CO document &1 &2 &4: more than 3 COEP items assigned to ACDOCA item

FINS_FI_MIG123 - Overview

• Message type: E = Error

• Message class: FINS_FI_MIG - SAP S/4HANA Finance: Data Migration

• Message number: 123

• Message text: CO document &1 &2 &4: more than 3 COEP items assigned to ACDOCA item

What causes this issue?

Item &V4& of CO document &V1& &V2& is to be migrated into table ACDOCA.
This items belongs to a group of COEP items of different CO versions.
Three previous items of this group have already been assigned to the new
ACDOCA item to be created in ledger &V3&, however.
If transfer prices are active, up to 3 different CO versions can exist,
resulting in groups of up to 3 COEP items that belong together. Such a
group can be migrated into a single ACDOCA item, but the group must not
contain more than 3 COEP items.

System Response

Item &V4& will not be migrated into table ACDOCA. Subsequent items that
might also belong to the same group will not be migrated as well.

How to fix this error?

Potential root causes are
Wrong configuration - more than 3 CO versions are assigned to ledger
&V4&.
Corrupt data in the old COEP table
Check the <DS:SIMG.FINSV_VERSN_LD>assignment of CO versions to ledgers
</> in the IMG.
Check the items of CO document &V1& &V2& using view V_COEP_ORI. Order
the items by fields BW_REFBZ (Posting Row in Operative Version) and
BUZEI (Posting Row), and search for BUZEI &V4&. If there are more than 3
items with the same BW_REFBZ value as this item, the old CO document is
corrupt. Contact SAP support to analyze the root cause so you can
implement a note that avoids further creation of such documents before
the upgrade.
In case the affected CO documents are from old fiscal years, you can
accept the errors in the migration cockpit. The affected items will not
be migrated to ACDOCA, so you will also get error messages in the next
migration step (R23), which you can accept as well. CO totals will be
corrected by migration of balances (step DLT), so there should not be an
impact on reporting and operations by the missing items.
You can also archive CO line items of the affected documents before
conversion to avoid these errors.

Error message extract from SAP system. Copyright SAP SE.

FINS_FI_MIG123 - Details

• The SAP error message FINS_FI_MIG123 indicates that during the migration of CO (Controlling) documents to the new Universal Journal (ACDOCA), there are more than three COEP (Controlling Document Line Item) items assigned to a single ACDOCA item. This situation arises because the Universal Journal is designed to consolidate financial and controlling data into a single line item, and it has specific constraints on how many COEP items can be associated with a single ACDOCA item.
  
  Cause:
  
  Data Structure Differences: The underlying data structure of CO documents in the classic system allows for multiple COEP items to be linked to a single document. However, in the Universal Journal, this is limited to three COEP items per ACDOCA item.
  Migration Process: During the migration process, if the system encounters a scenario where more than three COEP items are linked to a single ACDOCA item, it triggers this error.
  
  
  Solution:
  To resolve this error, you can take the