Why is the exchange with the site interrupted in 1s?

Question

1C

When exchanging small portions, everything goes fine. And with a full upload at 200-220 seconds, a break occurs and again an authorization request, which causes an error with a standard upload through commerceml

Answer 1

at full unloading, a break occurs at 200-220 seconds

Timeout settings on your web server.

Answer 2

I had such an assumption, I increased the timeout, removed nginx, increased everything that was possible in the server settings so that the file was accepted, contacted all support services, then changed 4 servers, and came to the conclusion that the problem was in 1s, file size or working time, something 1s does not suit