Characteristic &1 (&2) is only realigned, if not filled -> See long text

What causes this issue?

You want to realign characteristic &V1& (&V2&). Since operating concern
&V3& is (also) defined for account-based profitability analysis, you can
activate this type of profitability analysis in a controlling area and
fiscal year. In this case account-based line items are posted to G/L
line item table ACDOCA.
The characteristics in table ACDOCA are realigned as well in most cases.
However, certain characteristics are only updated in table ACDOCA if
they are initial, as otherwise this could lead to undesired side
effects. Such characteristics are:
Account assignments COPA_KOSTL (cost center), PSPNR (WBS element),
RKAUFNR (internal order), KAUFN / KDPOS (sales order and sales order
item) and KSTRG (cost object)
Fields KNDNR (customer), VKORG (sales organization), VTWEG (distribution
channel), SPART (division), WERKS (plant) and FKART (billing type)
Note that
characteristics KAUFN and KDPOS can only be filled in table ACDOCA by
using option <LS>Rederivation of ACDOCA Characteristics for Attributed
Line Items</>. Changes in profitability segments could lead to undesired
side effects as these are used in logistical processes. Hence these two
characteristics cannot be selected for setting fixed values or
rederivation.
characteristic KNDNR (customer) is <LS>always</> updated in case the
ACDOCA line item contains a true account assignment to profitability
segment.

System Response

Characteristic &V1& is only updated in segment level table &V4& but not
in table ACDOCA in case a value is already contained in the ACDOCA line
item to be realigned.

How to fix this error?

Note that this behavior leads to differences between your costing-based
and account-based profitability reporting regarding characteristic &V1&,
in case both types of profitability analysis are activated. The
costing-based reporting will show the realigned values whereas
account-based reporting will still show the originally posted values.
More information can be found in the online help under <LS>Profitability
Analysis -> Simplified Profitability Analysis -> Structures and Master
Data -> Master Data -> Realignment</>.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.