SAP Message SALV_X_API002 - Only first column with fieldname &1 will be considered in the excel

Diagnosis
Fieldname &V1& is used in 2 columns, but with different reference fields( &V2& respectively &V3& ).

System Response
The second column will not be considered when creating the excel.

Procedure
Use the same reference field or use different fieldnames (duplicate) forthe columns.