Enter the Warehouses screen and the datafield is filled automatically

Question

I have the following acumatic code where I want to fill a datafield with the name UsrSumVolumen and a new column called UsrVolumen is added, adding all the values of that column, the total will be put in UsrSumVolumen.

  protected void INLocation_RowSelected(PXCache cache, PXRowSelectedEventArgs e)
      {
        
              INLocation row = (INLocation)e.Row;
              INLocationExt rowExt = row.GetExtension<INLocationExt>();
          
              if (rowExt != null)
              {
                  // Accede a la nueva columna y realiza acciones adicionales
                  decimal? valorNuevaColumna = rowExt.UsrVolumen;
                  decimal? valorNuevaColumna2 = 78;
          
                  // Verifica si es necesario actualizar el objeto INSite
                  INSite orderInCache = Orders.Current as INSite;
          
                  if (orderInCache != null)
                  {
                      // Ajusta para actualizar el campo usrSumVolumen
                      Orders.Cache.SetValueExt<INSiteExt.usrSumVolumen>(orderInCache, valorNuevaColumna2);
                      PXTrace.WriteInformation("EMPEZAMOS - Nuevo valor: " + valorNuevaColumna2.ToString());
          
                      // Persiste el cambio
                      Orders.Cache.Persist(PXDBOperation.Update);
          
                      // Presiona el botón Save para asegurar que los cambios se reflejen en la interfaz de usuario
                      Orders.Cache.Graph.Actions.PressSave();
                  }
                  else
                  {
                      PXTrace.WriteInformation("orderInCache es nulo");
                  }
              }
              else
              {
                  PXTrace.WriteInformation("rowExt es nulo");
              }
  
            
       }

When reviewing the Last Requests, if it brings the requested values but does not insert it in UsrSumVolumen, can you help me solve it?

I also tried this code so that it would add automatically if it does, but only when I modify a grid field

[PXDBDecimal]
[PXUIField(DisplayName="volumen")]
[PXDefault(TypeCode.Decimal, "0.0", PersistingCheck = PXPersistingCheck.Nothing)]
[PXFormula(null, typeof(SumCalc<INSiteExt.usrSumVolumen>))]