Mixed Content for PHP laravel 5.4 pagination

We have an application setup behind the AWS load balancer and only the pages serving the pagination have issues with the Mixed Content warning.

We started with checking our .env file which has the correct APP_URL and all other configuration

Next, we checked the server headers and they also seem to be returning fine, Let me know if missing anything.

[REDIRECT_HTTTPS] => on 
[REDIRECT_STATUS] => 200 
[HTTPS] => on // added manually in apache configuration file
[HTTP_X_FORWARDED_FOR] => 14.143.xxx.xxx 
[HTTP_X_FORWARDED_PROTO] => https 
[HTTP_X_FORWARDED_PORT] => 443 

Next, we tried to enforce SSL but no luck

var/www/simpliv/app/Providers/AppServiceProvider.php under the boot function

$this->app['request']->server->set('HTTPS', true);
URL::forceScheme('https');

further read somewhere to check if application is getting secure protocol or not and tried this

Request::secure(); 
This return true

Screenshot of the issue. Unable to proceed further on how to fix this issue

Can provide Apache configuration and .htaccess file if required

via Chebli Mohamed