No WiFi when I use Kernel 6.4

You have not provided enough information about your system to help anybody figure out what the issue might be. If you are using a driver from AUR, you need to re-build that driver against the new Linux kernel/Kernel headers. Bumping an old thread isn’t the best idea either. A new thread would likely catch more attention, especially since the title was not edited and 6.4 is deprecated.

Please read: