Using fetch command in javascript in vs code

var _currentTime;
var _timeDifference = 0;
var d1;
var _currentTime


const _runAtFullTime = new Date(2021, 5, 1, 6, 10, 59, 920);
const _runAtEpoch = _runAtFullTime.getTime();

console.log(_runAtEpoch);



while (true) {
    _d1 = new Date();
    _currentTime = _d1.getTime();
    _trigger = _runAtEpoch - _currentTime;
    console.log(_trigger);

    if (_trigger <= 0) {
SendRequest();        
console.log('Successfull');
        break;
    }

}


function SendRequest() {

    var myHeaders = new Headers();
    myHeaders.append("Connection", "keep-alive");
    myHeaders.append("sec-ch-ua", "\" Not;A Brand\";v=\"99\", \"Google Chrome\";v=\"91\", \"Chromium\";v=\"91\"");
    myHeaders.append("sec-ch-ua-mobile", "?0");
    myHeaders.append("User-Agent", "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.77 Safari/537.36");
    myHeaders.append("Content-Type", "text/plain");
    myHeaders.append("Accept", "*/*");
    myHeaders.append("Origin", "Somethimg");
    myHeaders.append("Sec-Fetch-Site", "same-origin");
    myHeaders.append("Sec-Fetch-Mode", "cors");
    myHeaders.append("Sec-Fetch-Dest", "empty");
    myHeaders.append("Referer", "Something");
    myHeaders.append("Accept-Language", "en-US,en;q=0.9,fa;q=0.8,tr;q=0.7,de;q=0.6");
    myHeaders.append("Cookie", "cookiesession1=462A2B80VWZSTW26WF3QA0KE3VCYE820; DWRSESSIONID=YFe7h23EAe~OyKWGJDfDtCxusD5EkutPaDn; JSESSIONID=2B6C81A73B27F520D4D5BFC14BEAABA4");

    var raw = "callCount=1\n\nnextReverseAjaxIndex=0\n\nc0-scriptName=AjaxManager\n\nc0-methodName=saveMMTPOrder\n\nc0-id=0\n\nc0-param0=string:2B6C81A73B27F520D4D5BFC14BEAABA4\n\nc0-param1=string:\n\nc0-param2=string:IRO1GNBO0001\n\nc0-param3=string:15890062575775%20%20\n\nc0-param4=string:V\n\nc0-param5=string:2310\n\nc0-param6=string:0\n\nc0-param7=string:\n\nc0-param8=string:67140\n\nc0-param9=string:L\n\nc0-param10=string:J\n\nc0-param11=string:\n\nc0-param12=number:736467\n\nc0-param13=string:2\n\nc0-param14=number:1622694638706\n\nc0-param15=string:\n\nc0-param16=string:-1\n\nc0-param17=string:1\n\nc0-param18=null:null\n\nc0-param19=boolean:false\n\nc0-param20=string:1\n\nbatchId=10\n\ninstanceId=1\n\npage=%2FmmtpOrder.do%3F0.6389452411363696\n\nscriptSessionId=YFe7h23EAe~OyKWGJDfDtCxusD5EkutPaDn/xhH9gDn-Ar5jBbanv\n\n";

    var requestOptions = {
        method: 'POST',
        headers: myHeaders,
        body: raw,
        redirect: 'follow'
    };

    fetch("MyUrl", requestOptions)
        .then(response => response.text())
        .then(result => console.log(result))
        .catch(error => console.log('error', error));
    
}