I have AT&T internet and am required to use their dual modem/router. However since moving to my new apartment, internet does not work except when I use my TP Link Archer C7 router. 
 

Ive have been trying to connect to the router's management page to reset thr network name and password and I'm unable to do so. I am connected to the router's wifi and anytime I try to go to tplinkwifi.net, 192.168.0.1, or use the Tether app, it says my device is not connected. I've tried wifi and Ethernet, set up the IP pass through, have reset the router and nothing has worked.