Now it works like a charm based on your suggestion. I never take a look at DNS setting under DHCP, because it always works with the previous firmware & setting. Thank you. TP-Link wrote @diporif Hi,...

@TP-Link Custom DNS not working, I tried to change it into my private dns (adguard on Raspi) 10.0.0.88 and deco will automaticaly hang, auto reboot, and change my deco IP 10.0.0.1 into 192.168.x.x....