Parallel processing: Invalid packet size, fixed to 50 --> Long text

What causes this issue?

Parallel Processing of Attributable Amount Determination for
Facilities: Invalid Packet Size
The size of the packet for parallel processing could not be determined
and/or is a negative number.
The packet size specifies how many single records are processed per
parallel task in end-of-day processing. In the case of facilities, the
facility transaction itself and each drawing counts as a single
transaction.

System Response

The packet size is set by the system to 50, and parallel processing of
attributable amount determination (= end-of-day processing) is
continued.

How to fix this error?

Maintain the values in the Default Risk menu
,,,,Tools --> End-of-Day Processing --> Parallel Processing (directly:
transaction JBMT2).

Procedure for System Administrators

Application development: FM: BUILD_FO_PACKETS_4PARALLEL

Error message extract from SAP system. Copyright SAP SE.