async function populateIframe(nonce) {
var html = await fetchAsync("https://api.paymentworkflowtech.com/v1/iframe?nonce=" + nonce);
var ifr = document.getElementById("iframe1").contentWindow.document;
ifr.open();
ifr.write(html);
ifr.close();
}
You can also set the IFrame src to the same URL as above.