Mavis wrote TD-W8951NB is brand new or it was working with your line? It is a synchonization issue between the modem and your ISP line. If the line works with another router, it should be a problem...

Model : Hardware Version : Not Clear Firmware Version : ISP : router can not access to the internet, 2. and 3. light diod dont want to shine, only second diod sometimes flash.After upgrade...