so i have connected this router aforementioned (TD- W8961N)as an access point router to my base router which is an archer c60 , so everything was working alright until today when i logged in to the base router gateway web interface and it threw out a warning message saying due to an address conflict on front end device the routers ip address has been changed to 192.168.1.1  and ever since that i cant either login to my AP router gateway webpage or connect to internet via wifi but when i use a lan wire out of this AP router and use it in my pc the internet works , have no idea whatsover . my base routers ip used to be 192.168.0.1 and 192.168.0.2 for my AP router (which i cant login into now ).

need urgent help on this , any and all help will be very appreciated 

Thanks