“Cache Zone Path” does not appear to be a Nginx cache zone directory

Even setting the correct path in the field I still get the
‘“Cache Zone Path” does not appear to be a Nginx cache zone directory’ error message.
Diggin into the code I noticed that the plugin checks whether the path has files, and if those files have a 32 digit name length, indicating that it′s a MD5 file. The problem is that most recent versions of Nginx creates within fastcgi_cache_path′s directory files with names in the format “3e6d7a44a600768543daac6ee4b4da0f.0000002806, thus causing the “validate_dirlist” function to return false.
I′m using nginx 1.15.3 on an Ubuntu server.