Jenkins send e-mail notification to github committers - github

Question

We want to send out e-mail notifications to our contributors if the Jenkins build was successful or not.
we are using the email extension plugin: https://plugins.jenkins.io/email-ext/
Notifications should be sent in the following cases:
The current build failed or is unstable
the current build is successful and the previous build failed or was unstable
I created a shared library with the following script
#!/usr/bin/env groovy
def call(String buildStatus = 'STARTED') {
buildStatus = buildStatus ?: 'SUCCESS'
def subject = "JENKINS NOTIFICATION - ${buildStatus}: Job '${env.JOB_NAME} [${env.BUILD_NUMBER}]'"
def details = """${buildStatus}: Job '${env.JOB_NAME} [${env.BUILD_NUMBER}]'"""
// Send email to user who has started the build
emailext(
subject: subject,
body: details,
attachLog: true,
compressLog: true,
recipientProviders: [[$class: 'RequesterRecipientProvider'], [$class: 'CulpritsRecipientProvider']]
)
}
In the Jenkinsfile I loaded the library shared-lib and I defined the sendNotification command in the post-block of the jenkinsfile:
#!groovy
#Library('shared-lib') _
pipeline {
agent any
stages{
stage('Checkout code base'){
steps{
checkout scm
}
}
stage('another stage'){
steps{
echo "do something"
}
}
}
post{
always{
sendNotifications currentBuild.result
}
}
}
Currently, the e-mail notifications are sent when I manually trigger a build at Jenkins, but when I push to GitHub and Jenkins build gets triggered, no e-mail notification is sent.
This is the log of the pipeline:
19:12:06 [Pipeline] emailext
19:12:06 Sending mail from default account using System Admin e-mail address
19:12:06 messageContentType = text/plain; charset=UTF-8
19:12:06 Request made to attach build log
19:12:06 Request made to compress build log
19:12:06 Adding recipients from project recipient list
19:12:06 Not sending mail to user noreply-github+ms#companyname.com with no permission to view NewSimple » MTEvent » master #203 Collecting change authors...
19:12:06 build: 203
19:12:06 adding author: noreply-github+ms
19:12:06 Not sending mail to user noreply-github+ms#companyname.com with no permission to view NewSimple » MTEvent » master #203Adding recipients from trigger recipient list
19:12:06 Successfully created MimeMessage
19:12:06 An attempt to send an e-mail to empty list of recipients, ignored.
PS: I don't know from where this email noreply-github+ms#companyname.com was pickup.
The correct email address should be myfirstname.lastname#companyname.com
Not sure what I have missed.
Any suggestions would be appreciated.