RTSOnderwater.BeginScene(OnderwaterSurface, OnderwaterView);

Texture OnderwaterTexture;
    RenderToSurface RTSOnderwater;
    Plane reflectPlane;

    public void RefractionTex(Device device, Matrix view, Matrix Projection)
    {
        RTSOnderwater = new RenderToSurface(device, cGlobal.WindowWidth, cGlobal.WindowHeight, Format.X8R8G8B8, true, DepthFormat.D24X8);
        OnderwaterTexture = new Texture(device, cGlobal.WindowWidth, cGlobal.WindowHeight, 1, Usage.RenderTarget, Format.X8R8G8B8, Pool.Default);
        reflectPlane = Microsoft.DirectX.Plane.FromPointNormal(new Vector3(0, -1f, 0), new Vector3(0, 1, 0));

        Surface OnderwaterSurface = OnderwaterTexture.GetSurfaceLevel(0);
        Viewport OnderwaterView = new Viewport();
        OnderwaterView.Width = cGlobal.WindowWidth;
        OnderwaterView.Height = cGlobal.WindowHeight;
        OnderwaterView.MaxZ = 1.0f;

        RTSOnderwater.BeginScene(OnderwaterSurface, OnderwaterView); // <--- Why does it fail on this line? (error in application)
        device.Clear(ClearFlags.Target | ClearFlags.ZBuffer, 0, 1.0f, 0);

            Matrix reflectViewMatrix = Matrix.Identity;
            reflectViewMatrix.Reflect(reflectPlane);
            reflectViewMatrix = reflectViewMatrix * view;

            device.Transform.View = reflectViewMatrix;
            device.Transform.Projection = Projection;

            device.ClipPlanes[0].Enabled = true;
            device.ClipPlanes[0].Plane = reflectPlane;
            device.RenderState.Clipping = true;

            // render scene
            //
    
            device.RenderState.Clipping = false;
            device.ClipPlanes[0].Enabled = false;

        RTSOnderwater.EndScene(Filter.None);

    }

1904: Direct3D9: :====> ENTER: DLLMAIN(0475e6e0): Process Attach: 00000770, tid=000014541904: Direct3D9: :====> EXIT: DLLMAIN(0475e6e0): Process Attach: 000007701904: Direct3D9: (INFO) :Direct3D9 Debug Runtime selected.1904: D3D9 Helper: Enhanced D3DDebugging disabled; Application was not compiledwith D3D_DEBUG_INFO1904: Direct3D9: (INFO) :======================= Hal HWVP Pure device selected1904:1904: Direct3D9: (INFO) :HalDevice Driver Style 91904:1904: Direct3D9: :BackBufferCount not specified, considered default 11904: Direct3D9: :DoneExclusiveMode1904: Direct3D9: (WARN) :Ignoring redundant SetTextureStageState. Stage: 0, State: 21904:1904: Direct3D9: (WARN) :Ignoring redundant SetTextureStageState. Stage: 0, State: 31904:1904: Direct3D9: (WARN) :Ignoring redundant SetTextureStageState. Stage: 1, State: 21904:1904: Direct3D9: (WARN) :Ignoring redundant SetRenderState - 2071904:1904: Direct3D9: (WARN) :Ignoring redundant SetTextureStageState. Stage: 0, State: 21904:1904: Direct3D9: (WARN) :Ignoring redundant SetTextureStageState. Stage: 0, State: 31904:1904: Direct3D9: (ERROR) :BeginScene, already in scene. BeginScene failed.1904: