Why is Apache not responding to 1C request during synchronization?

Question

Apache HTTP Server

During the synchronization of 1C with the site (uploading goods to the site), a large number of pictures are loaded by POST requests (1 picture - one POST request). At a certain moment, 1C makes a POST request to Apache (somewhere in the 1900th picture, and there are more than 2800 in total) and 1C does not receive a response from Apache at all. What is the problem and how can it be solved at all? Screen logs 1C:

Answer 1

File size?

Answer 2

Apache log?