Incompatible breakdown of items &1 and &2

What causes this issue?

If a contra item is broken down with type 4 (required breakdown: forced
entry of a value, no default value), the associated item for this
breakdown must also have breakdown type 4. If it does not, the
dependability of the contra posting cannot be guaranteed.
The contra item pair &V1& / &V2& does not meet this prerequisite. The
breakdowns are not compatible.

System Response

The item substitution between &V1& and &V2& cannot take place.

How to fix this error?

Make sure that items &V1& and &V2& should be a pair of contra items.
Also check the breakdown category assignments and their definitions in
Customizing for Consolidation.

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.