Why does Tor proxy hang in multi-threaded mode?

Question

C++ / C#

The parser in multi-threaded mode works through the tor proxy 127.0.0.1:9050
And I noticed that it freezes, or more precisely, it stops responding to requests and it is impossible to receive a response from the server through this proxy.
To be more precise, the parser needs to request 1000 pages and it works in 20 threads, so about 60 pages can be obtained without problems, and all other connections to subsequent pages fail.
At the same time, it works perfectly without a proxy, as well as an interesting point if the parser is launched on a linux machine using the torsocks command, for example:
torsocks ./parser
then everything also works perfectly, the problem occurs when I directly access 127.0.0.1:9050