Period &1 is not opened for budgeting

What causes this issue?

Period &V1& is not open for budgeting.

System Response

Processing stops.

How to fix this error?

If you do not want to post budget to this period, reset the
corresponding amount to zero.
If you want to post budget to this period, maintain necessary setting in
<DS:TRAN.FMOPER>Open Budgeting Periods</>

Error message extract from SAP system. Copyright SAP SE.