Company code & and CO area & have different currencies

What causes this issue?

Company code &V1& is managed in &V3&, controlling area &V2& in &V4&.

System Response

Assignments such as this are not permitted because exchange rate
fluctuations between postings to cost accounting and settlements from
cost accounting would lead to non-permitted value additions.

How to fix this error?

Check whether the assignment between company code &V1& and controlling
area &V2& is intended.
In Customizing, assign the same currency to controlling area &V2&.

Error message extract from SAP system. Copyright SAP SE.