I have read all the threads related to this problem but I can't solve it. https://developers.facebook.com/tools/debug/?q=https%3A%2F%2Fwww.fondoposte.it

I've changed the robots.txt https://www.fondoposte.it/robots.txt and tested the curl curl -i -H 'Accept: /' -H 'Range: bytes=0-40960' -H 'Connection: close' -A 'facebookexternalhit/1.1 (+http://www.facebook.com/externalhit_uatext.php)' https://www.fondoposte.it/

Nothing! Can anyone suggest me a solution, please?