Item category of item to be created/changed is missing - Process canceled

What causes this issue?

You wanted to change a handling unit item. The system did not copy the
type of the item that was to be changed.

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?

Inform your system administrator.

Procedure for System Administrators

If the error occurs in the general pack function in the foreground,
report the error to SAP.
In all other cases, check the input data of the pack function-module.

Error message extract from SAP system. Copyright SAP SE.