Write-Off of Collective Bill Items as a Separate Process with Simulation

What causes this issue?

Collective bill items are items that are grouped together in a
collective bill. In simulation mode, executing and testing the write-off
of collective bill items is only possible in a limited way as a separate
process. As a simulation, you can only execute the write-off as an
individual process (job).
If you parallelize the mass posting run in simulation mode, then it is
not possible, for technical reasons, to execute the separate write-off
of items that belong to a collective bill.

System Response

The system does not execute the additional process for simulating the
write-off of collective bill items.

How to fix this error?

In simulation mode, run the write-off run only as an individual job
(without parallel processing). To prevent runtime problems, ensure that
the number of items to be checked is not too large.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.