Request URL changes if I execute it in different thread

[rbdm-qnt]

In my program I need to do periodical get and post requests on different threads. At the beginning of my main I call RestClient::init(), then when I need to send a request I create it, I print it as:
std::cout << "Request url:\n" << request.url << "\n";

and then I assign it to my thread_pool to execute in another thread. The other thread calls execute() method in my Request struct:

[[nodiscard]] RestClient::Response execute() const {
switch (type) {
case get: { std::cout << " - Inside request.h get. URL:\n" << url << "\n"; return RestClient::get(url); }
default: { assert(false); }
}
}

The outputs from the first and second prints are as follows:
Request url in main thread:
https://api.bybit.com/private/linear/position/list

• Pushed to threadpool
• Inside request.h get. URL:
  t��t.com/private/linear/position/list

Of course, the request fails because of unkown url. I don't understand how is it possible that the assignment of the Request object to another thread could modify just the beginning of my url string. If I execute the same request in the main thread it works just fine, but I can't work with that in my program.