Error renove certificate

Hi, I want to renew the certificate and it gives me the following error:
Challenge request failed for domain http://www.doubleigroup.com.
I have changed the attributes of directories and subdirectories * / letsencrypt and * /. Well-know to 755.
Can you help me?
Thank you