Logs in nginx, blank are created but not updated

I am going crazy, the logs have stopped working, I have created them again, I have the subdomains with the logs enabled, I have reviewed the top-down configuration of nginx and it does not work, only one log works. created that puts error.log in / var / log / nginx and that if it is updated when you start nginx, the rest of logs are created according to how I have them configured in site-avalibles, but they are blank

An example of the created logs:

  

-rw-r ----- 1 www-data adm 0 May 26 10:42 blog_access.log

     

-rw-r ----- 1 www-data adm 0 May 26 10:42 blog_error.log

This is the only one that works:

  

-rw-r ----- 1 www-data adm 14591 May 26 12:40 error.log

I do not understand, because I have reviewed as I said nginx.conf and I searched for the whole team and I can not find where nginx tells you to create that log and I do not understand, the rest of the logs have the same permissions and owners, because they do not they work.