Please assign a regulatory account to natural account &/&

What causes this issue?

The <DS:RE.FERCR040>direct postings</> procedure posts the balances for
all balance sheet accounts, direct assigned cost elements, and profit
and loss accounts which are not cost elements to direct assigned
regulatory accounts. This assignment is missing for account &V2& in
company code &V1&.

System Response

The system sends an error when the balance on natural account &V2& for
the current period is unequal to zero. Otherwise you just get a
warning.

How to fix this error?

Please assign a regulatory account in the regulatory parameters.

Error message extract from SAP system. Copyright SAP SE.