Notifications are disabled by default after updating to Android 13 (API Level 33)

Question

I am using Cordova to build my App and wanted to send push notifications. Everything was working earlier and we were not able to receive notifications after we updated the App to Android 13 (API Level 33). Here is my config.

targetSdkVersion:
<preference name="android-targetSdkVersion" value="33"/>

Push Notification Plugin:
https://npmjs.com/package/@havesource/cordova-plugin-push

Here is the script for sending push notifications using Firebase Cloud Messaging(FCM) and PHP:
https://gist.github.com/danieldesouza/23d753e74c154cffab4f46f71fc7f217

There are two problems:

1. Notifications are not received even after enabling on the App settings (Img attached)
2. How can we ask the users to grant permission?

Android docs say about Notification runtime permission but I am not sure what it is.
https://developer.android.com/develop/ui/views/notifications/notification-permission

Please help!