Not working fully with Moodle 4.x (Tested on 4.1 and 4.2)

[sangeeyeah]

The plugin has stopped working fully with 4.x versions of Moodle.

Working :

[1] Plugin gets installed
[2] Payment gets processed
[3] Student gets enrolled into the course at the back-end

Not working :

[4] After successful payment, the script goes to 'itn.php' and only a white screen is displayed
[5] Notification to admin / student / teacher is not triggered
[6] The process gets stuck in 'itn.php'

Can you please make the corrections..