How to unload the DLL so that does not block a file on a disk?

I have DLL which reads and writes some text files. My main program writes a text file named Parameters.txt as an input data for DLL. I use LoadLibrarу() function to link DLL with my main program at the run time. After a function call from DLL, which reads Parameters.txt file and produce some output, I use FreeLibrary() function to unload DLL.

The problem is that after unloading DLL it still blocks Parameters.txt for further editing or removing.

#include <windows.h>

int main() {

// create Parameters.txt input data file
create_parameters_file(file_path, /*... some stuff to write in file ... */);

// function pointer alias
using FuncPtr = void (*)();
    
HINSTANCE hDLL;
// DLL function pointer
FuncPtr composition_func_ptr;

// load DLL
hDLL = LoadLibrary(dll_path);
if (!hDLL) return -1;
// getting function by name
composition_func_ptr = (FuncPtr)GetProcAddress((HMODULE)hDLL, "Composition");
if (!elements_in_system_func_ptr || !composition_func_ptr)  return -1;

// calling DLL function. It reads Parameters.txt and create some output text file 
composition_func_ptr();

// unload DLL
FreeLibrary(hDLL);

// create Parameters.txt input data file AGAIN
create_parameters_file(file_path, /*... some OTHER stuff to write in file ... */);

return 0;
}

And this is how create_parameters_file() looks like:

void create_parameters_file(const std::string& file_path, /* stuff to write */)
{
bool file_opened = true;
std::ofstream out_file(file_path);
file_opened = out_file.is_open(); // this returns FALSE after DLL function call
out_file << ...
out_file.close();
}

Is there any way to unload DLL completely so it cannot block the file?

I circumvented the problem by calling an auxiliary application via CreateProcess() and loading DLL there. Looks cumbersome, but makes work buggy DLL.