@koldLight doing a google search for “nginx net::ERR_INCOMPLETE_CHUNKED_ENCODING” it sounds like it could be a permissions problem on your server.
When nginx proxies a file over a particular size it can write it to disk as a temporary file, if the permissions on it’s directory are incorrect then it can result in the error you’re seeing. There’s a related stack overflow answer here ruby on rails - net::ERR_INCOMPLETE_CHUNKED_ENCODING nginx - Stack Overflow
If it doesn’t seem to be that, maybe look into the resource usage on your server to make sure you’re not hitting any memory or disk space limits.