Controlling area and op. concern have different fiscal year variants

What causes this issue?

Controlling area &V1& and operating concern &V2& have different fiscal
year variants (&V3& and &V4&). However, for cost center assessment,
settlement, and many other types of postings to Profitability Analysis,
the controlling area and the operating concern must have identical
fiscal year variants, otherwise error messages or serious data
inconsistencies can occur.

System Response

The assignment made between controlling area &V1& and operating concern
&V2& cannot be saved.

How to fix this error?

Ensure that the controlling area and the operating concern have the
same fiscal year variant.

Error message extract from SAP system. Copyright SAP SE.