Wrong fulfillment quantity of POB &1 from BAdI call &2,deferral method &3

What causes this issue?

This error may be caused by the following:
The total reported quantity is not equal to
IS_DEFERRAL_METHOD-REPORTED_QTY.
The sum of the reported quantity (the numerator of the reported quantity
/ the denominator of the reported quantity) is not equal to
IS_DEFERRAL_METHOD-REPORTED_QTY.

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?

Please adjust your BAdI logic.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.