Man.maint.year earlier than closed fiscal year & (Correct)

What causes this issue?

The manual maintenance year must be the same or later than the last
year, &V1&, in which the base insurance year was updated.
This year is displayed during master data maintenance. It is either
the last closed fiscal year, or, when a year-end closing has already
been carried out, it is the last updated base insurance year.

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?

Correct your entry.

Error message extract from SAP system. Copyright SAP SE.