Message Box is not working inside WM_COMMAND! (WIN32 API) - c++

Question

I am new to Win32 API and trying to learn it. I was successful to create a window and it works perfectly.
I added a button to it and want to show a message box when clicked. The button works perfectly but the message box in WM_COMMAND does not appear at all and the code below message box does not get executed as well.
I have checked online for how to do it and it seems to work for them but not me.
Here is the code
#include <Windows.h>
#include <tchar.h>
#include <stdlib.h>
#include <string.h>
WNDCLASSEX wcex;
static TCHAR szWindowClass[] = _T("DesktopApp");
static TCHAR szTitle[] = _T("First Application");
HINSTANCE hInst;
LRESULT CALLBACK WndProc( HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);
int CALLBACK WinMain(_In_ HINSTANCE hInstance,_In_opt_ HINSTANCE hPrevInstance,_In_ LPSTR lpCmdLine,_In_ int nCmdShow)
{
wcex.cbSize = sizeof(WNDCLASSEX);
wcex.style = CS_HREDRAW | CS_VREDRAW;
wcex.lpfnWndProc = WndProc;
wcex.cbClsExtra = 0;
wcex.cbWndExtra = 0;
wcex.hInstance = hInstance;
wcex.hIcon = LoadIcon(hInstance, IDI_APPLICATION);
wcex.hCursor = LoadCursor(NULL, IDC_ARROW);
wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
wcex.lpszMenuName = NULL;
wcex.lpszClassName = szWindowClass;
wcex.hIconSm = LoadIcon(wcex.hInstance, IDI_APPLICATION);
if (!RegisterClassEx(&wcex))
{
MessageBox(NULL, _T("Call to Register Failed"), _T("Windows Desktop Guided Tour"), NULL);
return 1;
}
hInst = hInstance;
HWND hwnd = CreateWindow(szWindowClass, szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 500, 500, NULL, NULL, hInstance, NULL);
if (!hwnd)
{
MessageBox(NULL, _T("Failed to create a window"), _T("Windows Desktop Guided Tour"), NULL);
return 1;
}
ShowWindow(hwnd, nCmdShow);
UpdateWindow(hwnd);
MSG msg;
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}
return (int)msg.wParam;
}
HWND button;
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
PAINTSTRUCT ps;
HDC hdc;
TCHAR greeting[] = _T("Hello world! This is the first ever application window created by dumb Bhavin.");
switch (message)
{
case WM_CREATE:
button = CreateWindow(_T("BUTTON"),_T("1") ,WS_TABSTOP | WS_VISIBLE | WS_CHILD | BS_DEFPUSHBUTTON, 100, 40, 50, 30, hWnd, (HMENU)1, NULL, NULL);
break;
//////////////////////////////////THIS IS WHERE THE ISSUE IS///////////////////////////////////////////
case WM_COMMAND:
{
if (LOWORD(wParam) == 1)
{
OutputDebugString(_T("The compiler executes this! That means the button is working"));
MessageBox(NULL, L"Here it is", L"ok", NULL); //Message box does not appear at all. The code below it does not execute at all.
OutputDebugString(_T("The compiler DOES NOT execute this!"));
}
break;
}
//////////////////////////////////////////////////////////////////////////////////////////////////////
case WM_PAINT:
// hdc = BeginPaint(hWnd, &ps);
// TextOut(hdc, 5, 5, greeting, _tcslen(greeting));
EndPaint(hWnd, &ps);
break;
case WM_DESTROY:
PostQuitMessage(0);
break;
default:
return DefWindowProc(hWnd, message, wParam, lParam);
break;
}
return 0;
}
Edit 1:
Here is a small video of what exactly happens.
Error Video
Note : I passed hWnd parameter in this instead of NULL. Passing hWnd as first Parameter does not help either.

Answer 1

The issue was my half-implemented WM_Paint. Uncommenting the BeginPaint line solves the problem.
or, passing it directly to DefWindowProc as return DefWindowProc(hWnd, message, wParam, lParam); works too.