Login fails with HTTPS

[ecmdevelopers]

Contenta home page loads fine with both HTTP and HTTPS. However Login fails with 403 Forbidden error with HTTPS and page displays error "Not allowed". Login works fine with HTTP.

I have load balancer (AWS ALB) as the front to my web server which terminates HTTPS.

I see below code in drupal.conf, but not sure why it is failing.

if ($http_x_forwarded_proto = 'https') {
set $fastcgi_https "on";
}

NGINX error log has below error...
2019/04/05 17:04:04 [debug] 195#0: *1591 event timer add: 4: 60000:1554483904994
2019/04/05 17:04:05 [debug] 195#0: *1591 http upstream request: "/contenta/web/user/login?"
2019/04/05 17:04:05 [debug] 195#0: *1591 http upstream process header

2019/04/05 17:04:05 [debug] 195#0: *1591 http fastcgi parser: 0
2019/04/05 17:04:05 [debug] 195#0: *1591 http fastcgi header: "Status: 403 Forbidden"
2019/04/05 17:04:05 [debug] 195#0: *1591 http fastcgi parser: 0

[pcambra]

I have not really tried the https workflow, it'd be awesome to fix it/document it, PR's are very welcome :)