Home and Garden Why is my ATT router blinking red? Why is my ATT router blinking red? The gateway is connected to our network. ... The gateway has been trying to connect to our network for more than three minutes. Flashing red. The gateway can't connect to our network, or isn't detecting a DSL signal.2020-06-23 Related Posts:Is DSL and WIFI the same thing?Will I lose internet if I reset my router?What can I make with a router table?How do I fix the blinking lights on my modem?