It was there since first install but I resolved to usb tethering for a long time. I will try the recommendations and update. Also the wifi is nearly perfect when I connect to the hotspot on mobile. But I want it work with the D-Link modem at home. Other than mobile hotspot, I tried two different D-Link modems and the problems persists.
Edit: I tried everything given here Realtek RTL8822CE Wifi - limited connectivity - #5 by tbg except changing kernel