Profit center &1/&2 not maintained completely between &3 and &4

What causes this issue?

The profit center exists, however, it has not been maintained for the
entire period.

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?

Check your entry. If necessary, you must create the profit center for
any gaps in the period.

Error message extract from SAP system. Copyright SAP SE.