After an update the WiFi stopped working

I installed a VPN a few days ago, not for the first time on a laptop. Everything was working fine and then I decided I didn't need it and deleted it. After that, an update for the laptop was available and so I updated it and went to sleep. The next day the WiFi stopped working. If it connected, I would try to search something on any browser and it would say that the Internet isn't working. Often it can also shut off and on and you can see the icon for WiFi connection appearing and disappearing as you're searching for something. I haven't been able to solve this problem with simple reseting of laptop, reseting of WiFi settings, trying different networks for connecting... What should I do?