Asus RT-AC3100 : No routing on Wifi

Hi guys,

I don't know if it's the right section but I have an issue :
A device connected on 5Ghz wifi cannot broadcast and find a device connected on 2.4Ghz.

For exemple, my Google devices are connected on 2.4Ghz, in Google home you can see it but impossible to manage, if I stop 5Ghz and my cell force to connect 2.4Ghz, no pb.

Another one, I have an application for my TV, if my cell is on 5Ghz and my TV on the 2.4Ghz, impossible to connect. I stop the 5Ghz and force my cell to connect to...

Asus RT-AC3100 : No routing on Wifi