The asus is forwarding DHCP requests to the Sky router so clients will be able to access your network. What I think you need to do is set the Asus to router mode, if it can take WAN over Ethernet then connect the Ethernet WAN port to the sky router, set a static IP in the WAN config on the Asus so it's valid with the Sky router e.g. if the sky router has 192.168.0.1 as its management page set the Asus IP to 192.168.0.2, subnet 255.255.255.0, gateway/DNS 192.168.0.1.
Then find the LAN/DHCP section in the Asus and set a different subnet i.e. 192.168.5.x so any clients connected to the Asus are given an IP such as 192.168.5.10. This way because the subnet issued by the Asus is different from that issued by the sky router and on a 255.255.255.0 mask they cannot communicate with one another.
I've had to hurriedly type this for you so can try help some more if you need it when I'm not late going out!
Hi, sorry for the massive delay in getting back, but I have been trying loads of different ways but still cant do it.
I can do the first part but when I look in my lan/dhcp section on the asus, I have ip pool starting address and ip pool ending address, I have tried putting in 192.168.5.0 as the starting address but when I click save it say address is not valid.
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