Google pie charts add rows - pie chart didn't rendered

I have this JS file in asp.netcore. I'm trying to generate a pie chart from my database and there is only 1 row of data. I'm not getting any errors but only the title gets rendered but not pie chart. My JS code

google.charts.load('current', { 'packages': ['corechart'] });
google.charts.setOnLoadCallback(drawChart);
function drawChart() {
    $.ajax({
        url: '/Index?handler=GlobalChartData',
        dataType: 'json',
        contentType: 'application/json',
        type: 'GET',
        success: MyChart
    });
    function MyChart(globalData) {
        var data = new google.visualization.DataTable(globalData);
        data.addColumn('string', 'GlobalCases');
        data.addColumn('number', 'Data');
        data.addRows([
            ['NewConfirmed', globalData.NewConfirmed],
            ['NewDeaths', globalData.NewDeaths],
            ['NewRecovered', globalData.NewRecovered],
            ['TotalConfirmed', globalData.TotalConfirmed],
            ['TotalDeaths', globalData.TotalDeaths],
            ['TotalRecovered', globalData.TotalRecovered]
        ]);
        var options = { 'title': 'Global Covid Data' };
        var chart = new google.visualization.PieChart(document.getElementById('ChartForGlobal'));
        chart.draw(data, options);
    };
}

my c# code

public JsonResult OnGetGlobalChartData()
        {
            var globalData = _context.GlobalContexts.ToList();
            return new JsonResult(globalData);
        }

Edit: In add rows, globalData.NewConfirmed -> NewConfirmed is undefined and so are the others.

I changed my add rows to

for (var i = 0; i < globalData.length; i++)
        {
            data.addRows([
                ['NewConfirmed', Number(globalData[i].NewConfirmed)],
                ['NewDeaths', Number(globalData[i].NewDeaths)],
                ['NewRecovered', Number(globalData[i].NewRecovered)],
                ['TotalConfirmed', Number(globalData[i].TotalConfirmed)],
                ['TotalDeaths', Number(globalData[i].TotalDeaths)],
                ['TotalRecovered', Number(globalData[i].TotalRecovered)]
            ]);
        }

Now my chart is generated. Thank you @Swati.