Form code, not working on external websites

I need to see the generated tab to be of help.

sure,
https://www.facebook.com/darbouk/app_208195102528120

The submission is blocked because the data are sent to your site via https while the page is received in https. Try to change the form action to https

my site doesn’t support the https, when i change it in the tab, it says

SSL protocol error.

Facebook requires HTTPS and is proxying your page. I don’t know how you can post using their proxy (if possible).

ok, is there an easy way to convert all my main website in to https?

the https requires a certificate and an installation of that certificate and the support by the provider (usually even with a dedicated ip). You should ask the provider a quote for that.