Start of results analysis changed from period & to &

What causes this issue?

The start of results analysis is usually the period in which the object
was opened for which <DS:GLOS.WIP_calculation>WIP calculation</> or
<DS:GLOS.results_analysis>results analysis</> is to be carried out.
If you enter a results analysis period which falls before this, then
the start of results analysis is reset accordingly.

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?

Error message extract from SAP system. Copyright SAP SE.