How are you connecting the 2 devices, LAN to LAN or LAN to WAN?
The connection is Ethernet port 1 Hub2 to Wan port 1 security gateway.
I have to mention I tried all 4 Ethernet ports on hub all to wan1.
Then you either need to give the Unifi a static IP address outside of the DHCP range of the hub (say 192.168.1.10) and Gateway address of 192.168.1.254 or set the Unifi WAN port to DHCP and let it get the address and gateway from the Hub's DHCP server.
Set the DNS details to either your DNS provider of choice or 192.168.1.254 to use BT
Hello again,
I have been tried to give an static IP out of DHCP range as 192.168.1.10, using the gateway as per my hub 192.168.1.254 and make the connection to all ports on hub and still nothing and aslo I try to use the DHCP and still no connection. I have been tried all sort of address and port connection to the Hub and still no internet connection. I also activate the FTTP on port 4 and still nothing. I am really lost.
Unless you have FTTP (in which case LAN port4 needs to be connected to the ONT), FTTP mode should be set to off.
There is nothing you can configure on the Hub, the problem lies with the configuration of the Unifi. You might be better served posting on the Unifi forum.