Browser is not adding cookie on some requests - node.js

Question

We are running an application (local app) inside another application (moodle) as a plugin.
What happens is when our app tries to access the backend graphql it doesn't add the cookies but the cookie is available on document.cookie before the request is sent. Also before the app is opened in the iFrame there are few requests made from moodle to backend server and the browser adds the cookie to those request.
Following are the request headers
moodle -> backend
Host: graphql.app.home
Connection: keep-alive
Pragma: no-cache
Cache-Control: no-cache
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.198 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
Sec-Fetch-Site: cross-site
Sec-Fetch-Mode: navigate
Sec-Fetch-Dest: iframe
Referer: https://moodle.home:8443/
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9
Cookie: cb_ltiid=s%3AF0FJpsc8bVe9ZqyLzgNgK7flKfGf4W7u.2GL43c7XLV11BzHXCS%2B7AvQKBAS9xg%2BNc7gaj264%2Bks
app (from moodle iFrame) -> backend
Host: graphql.app.home
Connection: keep-alive
Content-Length: 118
Pragma: no-cache
Cache-Control: no-cache
accept: */*
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 11_0_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.198 Safari/537.36
content-type: application/json
Origin: https://app.home
Sec-Fetch-Site: same-site
Sec-Fetch-Mode: cors
Sec-Fetch-Dest: empty
Referer: https://app.home/
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9
Thanks for help

Answer 1

It was issue with fetch not sending the header because of
fetch won’t send cookies, unless you set the credentials init option.
(Since Aug 25, 2017. The spec changed the default credentials policy
to same-origin. Firefox changed since 61.0b13.)
solution was to pass credentials: 'include' to fetch options