Hi. I have been having problem extending my wifi. I have an existing asus lyra aimesh router connected with my modem via LAN. And i just bought a deco m4 to extend the wifi coverage as there is a dead zone in my house. Been trying to connect the deco m4 to the modem but it js telling me there is no internet connection , and i've also tried to connect via LAN with the asus lyra router as access point but still no internet connection. Really need some help with this.

current network

main modem - asus lyra router - asus lyra node 1 via wifi

trying to extend to be

main modem - asus lyra router - deco m4 main via LAN and asus lyra node 1 via wifi - deco m4 node 1

thank you