Facebook debug problem

Hi
I face problem with my site. Whenever I want to share my article on my FB page. I get 404 page.
When I run Facebook debug tool I see:
original page http://www.mydomain...
og:url http://mydomain...
Og url doesn't exist, it just redirects to 404, I use only "www" pages.

Here is full picture...

image-fb-debug.jpg

What am I doing wrong?

Thanks for help

The problem may be related with your Facebook APP ID configuration. Please make sure that you use proper domain in facebook settings sometimes you should use www.domain.com instead of http://domain.com, it all depends of your domain configuration.

Thanks for help.
I deleted all my Facebook apps, but there is still problem.
Some time ago I have installed JFBC, I deleted it. The problem is still there

In my htaccess. I have redirect to www version of my site.
When I enter the page of article without www, I do not get redirected, instead of it I see 404.

What should I try more?

Thanks for help

When I enter the page of article without www, I do not get redirected, instead of it I see 404.

This is something that you need to configure in domain settings. Did you try to contact with your hosting provider?