Declaration period was entered manually

What causes this issue?

The declaration period was entered manually for this declaration.
As a rule, declarations should only be carried out using the automatic
defaulting of periods and fiscal year. A declaration period may only be
entered manually if a price list modification with change of currency
has taken place within a settlement period.

System Response

The action was logged.

How to fix this error?

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.