Failed to create render target view DirectX 11 - c++

Question

This is my code. The final if is true so i get the messageBox that tells my the createRenderTargetView is failed. I'm pretty new to this and i searched online a lot, but found nothing, do you have any tips? Thanks.
This is the probelmatic part
//feature levels
D3D_FEATURE_LEVEL featureLevels[6]{
D3D_FEATURE_LEVEL_11_0,
D3D_FEATURE_LEVEL_10_1,
D3D_FEATURE_LEVEL_10_0,
D3D_FEATURE_LEVEL_9_3,
D3D_FEATURE_LEVEL_9_2,
D3D_FEATURE_LEVEL_9_1,
};
//swap chain
ZeroMemory(&m_swapChainDesc, sizeof(DXGI_SWAP_CHAIN_DESC));
m_swapChainDesc.BufferDesc.Height = 600;
m_swapChainDesc.BufferDesc.Width = 800;
m_swapChainDesc.Windowed = true;
m_swapChainDesc.BufferCount = 1;
m_swapChainDesc.OutputWindow = hwnd;
m_swapChainDesc.Flags = 0;
m_swapChainDesc.SampleDesc.Count = 1;
m_swapChainDesc.SampleDesc.Quality = 0;
m_swapChainDesc.BufferUsage = DXGI_USAGE_DISCARD_ON_PRESENT;
m_swapChainDesc.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
m_swapChainDesc.BufferDesc.RefreshRate.Numerator = 0;
m_swapChainDesc.BufferDesc.RefreshRate.Denominator = 1;
UINT createDeviceFlags = 0;
m_swapChainDesc.BufferDesc.ScanlineOrdering = DXGI_MODE_SCANLINE_ORDER_UNSPECIFIED;
m_swapChainDesc.BufferDesc.Scaling = DXGI_MODE_SCALING_UNSPECIFIED;
m_swapChainDesc.SwapEffect = DXGI_SWAP_EFFECT_DISCARD;
#if defined(DEBUG) || defined
(_DEBUG)createDeviceFlags |= D3D11_CREATE_DEVICE_DEBUG;
#endif*/
//creazione device e swapchain
/*hr=D3D11CreateDeviceAndSwapChain(nullptr, D3D_DRIVER_TYPE_HARDWARE, 0, 0, 0, ARRAYSIZE(featureLevels), D3D11_SDK_VERSION,
&m_swapChainDesc, &m_swapChain, &m_device, featureLevels, &m_deviceContext );
*/
D3D_FEATURE_LEVEL featureLevel;
hr = D3D11CreateDevice(0, D3D_DRIVER_TYPE_HARDWARE, 0, createDeviceFlags, featureLevels, 6, D3D11_SDK_VERSION, &m_device, &featureLevel, &m_deviceContext);
if (FAILED(hr))
MessageBox(0, L"D3D11CreateDevice Failed.", 0, 0);
IDXGIDevice *dxgiDevice = 0;
hr=m_device->QueryInterface(__uuidof(IDXGIDevice), (void**)&dxgiDevice);
if (FAILED(hr))
MessageBox(0, L"Fallita queryInterface", 0, 0);
IDXGIAdapter *dxgiAdapter = 0;
hr=dxgiDevice->GetParent(__uuidof(IDXGIAdapter), (void**)&dxgiAdapter);
if (FAILED(hr))
MessageBox(0, L"Fallito getParent", 0, 0);
IDXGIFactory *dxgiFactory = 0;
hr=dxgiAdapter->GetParent(__uuidof(IDXGIFactory), (void**)&dxgiFactory);
if (FAILED(hr))
MessageBox(0, L"Fallito getParent", 0, 0);
IDXGISwapChain *m_swapChain;
hr=dxgiFactory->CreateSwapChain(m_device, &m_swapChainDesc, &m_swapChain);
if (FAILED(hr))
MessageBox(0, L"Failed crating the swap chain", 0, 0);
dxgiAdapter->Release();
dxgiDevice->Release();
dxgiFactory->Release();
ID3D11RenderTargetView *m_renderTargetView;
ID3D11Texture2D *m_backBuffer;
hr=m_swapChain->GetBuffer(0, __uuidof(ID3D11Texture2D), reinterpret_cast<void**>(&m_backBuffer));
if (FAILED(hr))
MessageBox(0, L"Failed get buffer", 0, 0);
hr=m_device->CreateRenderTargetView(m_backBuffer, NULL, &m_renderTargetView);
if (FAILED(hr))
MessageBox(0, L"Failed to create rendertargetview", 0, 0);