What causes this issue?

For the recycling partner Belland Vision, a monetary declaration is
not possible in the specified period since price lists have to be
maintained in different recycling partner currencies. Up to 31.12.2001
the recycling partner currency was DEM, as of 01.01.2002 the currency is
Euro.

System Response

The declaration is terminated.

How to fix this error?

Enter a valid period for the declaration date, in other words, a
declaration period that occurs entirely before 01.01.2002 or entirely
after 31.12.2001.

Error message extract from SAP system. Copyright SAP SE.