2.4ghz not showing up after enabling QoS model #R6220

[3li]

After enabling QoS the 2.4ghz network wont show up. Everything seems fine on the router webpage but it’s not displaying only the 5ghz one shows up. I’ve disabled QoS and still not showing. I reset the router to factory and updated the firmware and it still isn’t showing. I’ve tried all the channels and modes. Still nothing. Only 5ghz shows up and I cannot connect to the 2.4ghz on anything just wont show up. It was working perfectly before.