BitBlt Not returning image

public Bitmap GetScreenShot()
{
    try
    {
        Screen.BitBlt(_hdcDest, 0, 0, CaptureWidth, CaptureWidth, _hdcSrc, _zones[0], _zones[1], 0x00CC0020);
        return (Bitmap)_bitmap.Clone(); // Return a copy to avoid threading issues
    }
    catch (Exception ex)
    {
        Debug.WriteLine($"Capture Error: {ex.Message}");
        return null;
    }
}

public Grabber() {
// Takes half of the screen width and height and makes box in the middle
  _zones = CalculateGrabZone(HalfScreenX, HalfScreenY, GrabZone);

CaptureHeight = _zones[3] - _zones[1];
CaptureWidth = _zones[2] - _zones[0];


_Enabled = true;

_bitmap = new Bitmap(CaptureWidth, CaptureHeight);
_gDest = Graphics.FromImage(_bitmap);
_hdcDest = _gDest.GetHdc();
_hdcSrc = Screen.GetDC(IntPtr.Zero);
}