Need to Clear selected information on Pagination

Good Morning Community,

I've been experimenting with a simple interface where I need to clear the selected results when going to another page.

I suspect it is in the index/batch size area, however I'm not having any luck.

a!localVariables(
  local!selection : null,
{
  a!sectionLayout(
    label: "Test Details",
    labelSize: "SMALL",
    labelColor: "#007958",
    contents: {
      a!columnsLayout(
        columns: {
          a!columnLayout(
            contents: {
              a!gridField(
                label: "",
                labelPosition: "ABOVE",
                data:{ 
                { ONE: "One", Pho: "Alpha", Is_Primary: "True" },
                { ONE: "Two", Pho: "Beta", Is_Primary: "False"},
                { ONE: "Three", Pho: "Gamma", Is_Primary: "True" },
                { ONE: "One", Pho: "Alpha", Is_Primary: "True" },
                { ONE: "Two", Pho: "Beta", Is_Primary: "False" },
                { ONE: "Three", Pho: "Gamma", Is_Primary: "True"}
                },
                columns: {
                  a!gridColumn(
                    label: "A",
                    value: fv!row.ONE
                  ),
                  a!gridColumn(
                    label: "B",
                    value: fv!row.Pho
                  ),
                  a!gridColumn(
                    label: "C",
                    value: fv!row.Is_Primary
                  )
                },
                validations: {},
                pageSize: 4,
                selectable: true,
                selectionstyle: "ROW_HIGHLIGHT",
                selectionSaveInto: {
                  a!save(
                    local!selection,
                    index(
                      fv!selectedRows,
                      length(fv!selectedRows),
                      null
                    )
                  )
                }
              )
            }
          )
        },
        alignVertical: "TOP",
        spacing: "STANDARD"
      )
    },
    isCollapsible: false,
    isInitiallyCollapsed: false,
    divider: "BELOW",
    dividerWeight: "THIN",
    dividerColor: "#dddddd"
  ),
  a!sectionLayout(
    label: "Programs",
    labelSize: "SMALL",
    contents: {
      a!columnsLayout(
        columns: {
          a!columnLayout(
            contents: {
              a!gridField(
                label: "",
                labelPosition: "ABOVE",
                data:  
                { 
                  { Program_Type: "Xray" },
                  { Program_Type: "Zulu" }
                }
                ,
                columns: {
                  a!gridColumn(
                    label: "Program Type",
                    value:  fv!row.Program_Type
                  )
                }
              )
            }
          )
        }
      )
    },
    showWhen: local!selection.is_Primary = "true",
    isCollapsible: false
  )
}

)