Diagnosis
The internal field length of field &V1& is shorter intable/structure &V3& than in table/structure &V2&.
There is a danger that data will be lost when data is transferred fromV2 to v3.

Procedure for System Administration
Use the same data element for field &V1& in both tables/structures.
Use the ABAP Dictionary(transaction SE11) for modifying the table/structure.