How to fix 404 error when adding on Facebook?

Question

Facebook

Hello. I ran into a problem that I have never encountered before.
In general, when sharing a site on Facebook, it gives a 404 error where it says that the page was not found. Google Plus and Twitter pull everything up nicely. Pulls up only the main page, all the rest are lost .. Checked the URLs, everything works. Canon did too.
Registered everything og: but to no avail .. Tell me, who faced such a problem?
Screenshot:

Thank you in advance.

Answer 1

logs and once again
you check the logs with the logs of the page that was found