Amazon S3 - server responded with 0 code

I am trying to upload multiple files (50 files - 9.4MB size per file) at a time (using dropzone) into an amazon s3 bucket. A few minutes later, having received the error "The server responded with code 0". My ruby ​​version is 2.2.2, rails 4.2 and carrier wave, Nginx and Unicorn servers.

When I select 50 files (9.4 MB for each file) after a few minutes, some files upload successfully, but some files fail to upload and don't get this error.

So what is the reason for this? What is the solution to the problem? Are there any plans I need to update to download large S3 files? because I need to upload files from 500MB to 1GB - 100 files at a time.