Process.Start create an instance of the app instead of running a process

i run the following code and instead of running the package exe (just some command line stuff wrote in .NET) i notice another instance of the existing app
does anyone had this and know how to solve it?

BTW, i printed out the package exe path and it looks OK but still there's a process with the same app name instead of the exec

   if (string.IsNullOrEmpty(package_exe_path))
            return true;

   Console.WriteLine(package_exe_path);

        var psi = new ProcessStartInfo
        {
            FileName = package_exe_path,
            Arguments = arguments,
            UseShellExecute = false,
            CreateNoWindow = true,
            ErrorDialog = false
        };

        try
        {
            var p = Process.Start(psi);

            if (p == null)  
            {

                return false;
            }
        }