Lot &1 has already been partially migrated with lot &2

What causes this issue?

Sample lot &v1& that you specified has already been partially migrated
with sample lot &v2&.

System Response

You can no longer process sample lot &v1&. The only remaining option is
complete migration with the target lot.

How to fix this error?

Check your entries.

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.