Error when sending object type &1 from SAP R/3 --> SAP APO

What causes this issue?

An error occurred within CIF postprocessing when sending objects from
SAP R/3 to SAP APO.
The error occurred in an object of type &V1&.
Document number: &V2&
Material: &V3&
Plant: &V4&

System Response

The sending of objects is terminated.

How to fix this error?

Use additional messages in the postprocessing log and in the SAP APO
application log for integration to determine the cause of the error.
Rectify the cause of the error and send the objects again.

Error message extract from SAP system. Copyright SAP SE.