I can not export html table with the SheetJs library solution?

Every time I click the button the saveAs function tells me in console that it is not defined.

$(".btn-buscar").click(function (e) {
    e.preventDefault();

    var workbook = XLSX.utils.book_new();
    var worksheet = XLSX.utils.table_to_sheet($("#tablaCotizaciones1")[0]);

    var wscols = [
        { wch: 20 },
        { wch: 14 },
        { wch: 17 }
    ];

    worksheet["!cols"] = wscols;

    $.each(worksheet, function (key, value) {
        if (key.startsWith("B")) {
            worksheet[key].z = "###0";
        } else if (key.startsWith("D")) {
            worksheet[key].z = "$###0";
        }
    });

    XLSX.utils.book_append_sheet(workbook, worksheet, "Coverage");

    var wopts = { bookType: "xls", bookSST: false, type: "binary", cellDates: false };
    var wbout = XLSX.write(workbook, wopts);

    function s2ab(s) {
        var buffer = new ArrayBuffer(s.length);
        var view = new Uint8Array(buffer);

        for (var i = 0; i != s.length; i++)
            view[i] = s.charCodeAt(i) & 0xFF;

        return buffer;
    }

    var fileName = $("#tablaCotizaciones1").text().replace(/[^a-z0-9\s]/gi, '') + ".xls";
    console.log(fileName);
    //saveAs(new blob([s2ab]),filename);
    saveAs(new Blob([s2ab(wbout)], { type: "application/octet-stream" }), fileName);

});