Laravel 5.4 with SSL

I developed a site with Laravel 5.4.

I just installed an SSL certificate and added this to my htaccess:

RewriteCond %{HTTP:Authorization} .
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]

I also added this in my AppServiceProvider:

URL::forceScheme('https');

When I go to mysite.co.za it changes to https but when I go to my admin section: mysite.co.za/admin it does not and it shows me an 'i' icon instead of a lock icon on the address bar.

Clicking on the 'i' icon says the site is not secured.

My host reply: This is most likely a configuration issue where the site is using mixed content. I have no idea what they mean and how to fix it.

Can anyone help please?

via Chebli Mohamed