c# - After changing screen resolution the cursor hover area is offset

I have the below code to change my 2nd display screen resolution. It all works fine and changes as expected. However once it has been changed my mouse/cursor is offset. eg the active location is not where the pointer shows on the screen.

Thoughts?

using System;
using System.Windows;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using System.Drawing;

[StructLayout(LayoutKind.Sequential)]
public struct DEVMODE1
{
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
public string dmDeviceName;
public short dmSpecVersion;
public short dmDriverVersion;
public short dmSize;
public short dmDriverExtra;
public int dmFields;

public short dmOrientation;
public short dmPaperSize;
public short dmPaperLength;
public short dmPaperWidth;

public short dmScale;
public short dmCopies;
public short dmDefaultSource;
public short dmPrintQuality;
public short dmColor;
public short dmDuplex;
public short dmYResolution;
public short dmTTOption;
public short dmCollate;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
public string dmFormName;
public short dmLogPixels;
public short dmBitsPerPel;
public int dmPelsWidth;
public int dmPelsHeight;
public int dmPosition;

public int dmDisplayFlags;
public int dmDisplayFrequency;

public int dmICMMethod;
public int dmICMIntent;
public int dmMediaType;
public int dmDitherType;
public int dmReserved1;
public int dmReserved2;

public int dmPanningWidth;
public int dmPanningHeight;
};



class User_32
{
[DllImport("user32.dll")]
public static extern int EnumDisplaySettings(string deviceName, int modeNum, ref DEVMODE1 devMode);
[DllImport("user32.dll")]
public static extern int ChangeDisplaySettings(ref DEVMODE1 devMode, int flags);
[DllImport("user32.dll")]
public static extern int ChangeDisplaySettingsEx(string lpszDeviceName, ref DEVMODE1 lpDevMode, IntPtr hwnd, ChangeDisplaySettingsFlags dwflags, IntPtr lParam);

public const int ENUM_CURRENT_SETTINGS = -1;
public const int CDS_UPDATEREGISTRY = 0x01;
public const int CDS_TEST = 0x02;
public const int DISP_CHANGE_SUCCESSFUL = 0;
public const int DISP_CHANGE_RESTART = 1;
public const int DISP_CHANGE_FAILED = -1;

[Flags()]
public enum ChangeDisplaySettingsFlags : uint{
    CDS_NONE = 0,
    CDS_UPDATEREGISTRY = 0x00000001,
    CDS_TEST = 0x00000002,
    CDS_FULLSCREEN = 0x00000004,
    CDS_GLOBAL = 0x00000008,
    CDS_SET_PRIMARY = 0x00000010,
    CDS_VIDEOPARAMETERS = 0x00000020,
    CDS_ENABLE_UNSAFE_MODES = 0x00000100,
    CDS_DISABLE_UNSAFE_MODES = 0x00000200,
    CDS_RESET = 0x40000000,
    CDS_RESET_EX = 0x20000000,
    CDS_NORESET = 0x10000000
}
}

namespace Resolution
{
class CResolution
{
    public CResolution(int iWidth, int iHeight)
    {

        DEVMODE1 dm = new DEVMODE1();
        dm.dmFormName = new String(new char[32]);
        dm.dmSize = (short)Marshal.SizeOf(dm);
        dm.dmPosition = 2;

        if (0 != User_32.EnumDisplaySettings(null, User_32.ENUM_CURRENT_SETTINGS, ref dm))
        {

            dm.dmPelsWidth = iWidth;
            dm.dmPelsHeight = iHeight;


            long result = User_32.ChangeDisplaySettingsEx("\\\\.\\DISPLAY2", ref dm, IntPtr.Zero, User_32.ChangeDisplaySettingsFlags.CDS_UPDATEREGISTRY, IntPtr.Zero);
        }
    }
}
}

-

 static void Main(string[] args)
    {


        Resolution.CResolution ChangeRes = new Resolution.CResolution(2560, 1600);

    }