back from DrillDown grid to linechart

I applied back button on drill down grid .getting redirected to linechart ... but whenever i am clicking on back button it is creating new layout with grid ... also making the required variables null while clicking back button,..

I just want to get redirected to linechart ....

a!columnLayout(
            contents: {
              a!buttonArrayLayout(
                align: "END",
                buttons: {
                  a!buttonWidget(
                    icon: "home",
                    label: "Back to User Logins",
                    style: "LINK",
                    submit: true,
                    value: "BACK",
                    saveInto: {local!backButton,
                    a!save(
                      ri!selectedDateRange,null()
                    )}
                  )
                }
              )
            }
            
          )
        }
      ),
      if(
        isnull(local!backButton),{},rule!VID_uiSectionLineChart(selectedValue:ri!selectedDateRange)
      )