How To Fix W8728 - Key already exists for change document object &

SAP Error Message - Details

• Message type: E = Error

• Message class: W8 - Workflow: Expressions, data flow

• Message number: 728

• Message text: Key already exists for change document object &

What causes this issue?

A structure should be created for the change document object which
corresponds to the key of a business object type.
There is already a structure for the change document object that makes
the change document object compatible with a business object type.

How to fix this error?

Only overwrite the existing structure if the link between the change
document object and the other business object type is no longer needed.
If the existing link remains, you must allocate the event a different
business object type. This business object type must have a key
structure identical to the change object type or a key structure
identical to the structure defined.

Error message extract from SAP system. Copyright SAP SE.