The Wi-Fi icon in the menu bar appears blank. When I open the network settings and click on "Turn on Wi-Fi", nothing happens.
I tried to disable the Wi-Fi service, clear it, reboot the MacBook, and re-add the service.
This update actually worked, but the problem returned after about thirty minutes.
Since then, I have just repeated the process every time the Wi-Fi turns off, but it's very awkward, and I hope it's not the only solution.
I am afraid that the fact that the WLAN shuts off again is a hardware problem.
After I received an answer to another user who had a similar problem, I also tried to "turn on the wireless card" using Terminal. It had no effect.
UPDATE: After restarting the MacBook, "Wi-Fi: No Hardware Installed" now appears and I can not create a new Wi-Fi service.