How to Add data continuously in excel using Jquery Code

var jsonData = [{ "Date: " : output, "Name: " : s2_name];

                // Save to excel
                var file_name = s2_name + "-" + output;
                saveExcel(jsonData, file_name);
                window.location.reload();
            };
        });

I have this code but every time I submit another file is being saved. it did not add to be previous excel file. please help me