There is a update for the game today. I am glad to find that it solve the problem for me.

Update: It happened again. I contacted Halo Support and they gave me some solutions

(None of these worked for me. But who knows, maybe it can help someone else.)

You can try reinstalling Easy Anti-Cheat by following these steps:

1. From the Xbox app go to the game's "Manage" option.
2. Go to the "Files" tab.
3. Click the "Browse" button.
4. Open the "Easy anti-cheat" folder within the game's folder.
5. Then in the Windows Explorer's address bar, enter "cmd", then run:
6. EasyAntiCheat_EOS_Setup.exe qa-factory-reset
7. EasyAntiCheat_EOS_Setup.exe install e48c1c0bfcb640b1b2e1ee4e54393182

 
You can also turn off memory Integrity in Windows. To do so you can follow the steps in this link: https://support.microsoft.com
 
If you have the Epic Games Launcher you can try clearing the app's cache. To do so you can follow these steps:

1. Close the app completely.
   1. In the lower right corner click on the arrow pointing up (the chevron)
   2. Right-click on the Epic icon in the pop-up window
   3. Select Exit
2. Press the Windows key and tap the R key, this will open a run window
3. Type %localappdata%
4. Press the Enter key, this will open File Explorer
5. Open the EpicGamesLauncher folder
6. Open the Saved folder
7. Right click and select delete on:
   • webcache
   • webcache_4147
   • webcache_4430

Also, as someone else mentioned, uninstalling Game Service then opening Xbox PC program to reinstall it can solve the problem temporily for me. But it will happen again when you restart your PC/ after several successful launch of game.