Diagnosis
Field &V1& is not in table/structure &V3&.
There is a danger that data will be lost when data is transferred fromV2 to v3.

Procedure for System Administration
Add all user-defined fields of table/structure &V2& to the CI include oftable &V3&. If SAP did not provide for a CI include in &V3&, create acorresponding append structure. Make sure that you define the fieldsexactly as in the original table/structure.
Use the ABAP Dictionary (transaction SE11) formodifying the table/structure.