2nd execute of iteration does not find port names.

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Visual-Studio

C++Builder

I setup the OnClick enumerator part like this:

ListBox1->Items->Clear();// <------- begin of 1st enumerate, from provided example
        res=BeginEnumeratePorts();
        while(TRUE)
         {
          if(!EnumeratePortsNext(res,buf))break;
          ListBox1->Items->Add(buf);
          i++;
         }
        EndEnumeratePorts(res);

ListBox1->Items->Clear();   // <------- begin of 2nd enumerate, identical to 1st one
        res=BeginEnumeratePorts();
        while(TRUE)
         {
          if(!EnumeratePortsNext(res,buf))break;
          ListBox1->Items->Add(buf);
          i++;
         }
        EndEnumeratePorts(res);

On the 2nd run, the enumerate fails to create the list done by 1st
1st list is
COM1
COM2

Why does the 2nd run not enumerate?

What I have tried:

I am using Borland C++ builder 5, and also exact same results using Visual Studio 2017 and VS2019.

I have examined the code, and all appears to be as documented by MS. There seems to be something static which is not being reset, for the 2nd run.