Following exceptions during incompleteness check of alloc.tab. &1,itm &2:

What causes this issue?

The exceptions listed below were raised during the incompleteness check
for allocation table &V1&, item &V2&.

System Response

The following messages come from the incompleteness log generated when
checking allocation table &V1&.

How to fix this error?

Check the messages below and make any necessary corrections, to allow
the proper update of the allocation table.

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.