By connecting the computer directly to the modem and bypassing the TP-Link router, you can ensure that the Internet is working If your TP-Link Router gets a WAN IP from the modem but no internet access.
Problem Description: Even though the router has been issued a valid IP address, there is no internet access after configuration.
Click on DHCP -> DHCP settings, then in the Primary DNS area, type 220.127.116.11 and click Save. Google's public DNS server, 18.104.22.168, is free and secure.
Turn off your modem and TP-Link router and wait one minute.