Number range &1 in co.code &2 for doc.type &3 must be defined as internal

What causes this issue?

Your fiscal year variant is defined with &V1& periods.
However, the system requires fiscal year variants that have either 12
or 24 periods in order to make an automatic assignment of the periods
to the calendar date.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Define your period control for this fiscal year variant manually in
FI-AA Customizing.

Error message extract from SAP system. Copyright SAP SE.