@David-TP Hi thank you for replying. my BE65 Deco is on version 1.1.6 and up to date at the moment. I swapped the X50 Deco which was the main router and had all the right configuration for ipv6 and was receiving an ipv6 address from my ISP SKY broadband and this was then giving this out to all the devices a Ipv6 addresses through DHCP. When the BE65 Deco turned on and connected as the main router I instantly saw that the IPv6 was no longer working but none of the settings in the internet connection changed at all which is very strange. 

MY setup is as follows: 

• Dynamic IP 
• Get Ipv6 address - Stateless 
• Prefix Delegation - Enabled 
• DNS address - Auto 
• Assigned Type - DHCPv6

I know SKY broadband doesn't use ipv6 DNS addresses yet so I know that is fine when they are not appearing but it is very strange that I am no longer receiving an Ipv6 IP address on the BE65 Deco 

  @David-TP Hi, Thank you so much for the help about this one. After looking at MAC address cloning this makes more sense to me that this could be affecting the BE65 from getting an IP address from the modem. I will try this when I get home from work today and see if this will clear the issue hopefully this will also clear the instability issue with the network as well once I clone the MAC address. 

Funny enough the Sky fibre help article you linked was my previous post when I was trying to set this up for the first time with my Deco x50 until I upgraded to the BE65 as the main router. 

  @David-TP I have just got home and done some testing. I have set the settings as follows:

Internet connection type - Dynamic IP

Get Ipv6 address - Stateful

Prefix delegation - Enabled 

DNS Address - Auto 

Assigned type - DHCPv6

This now populates an address prefix and an ip address in LAN info and I have checked and I have Ipv6 addresses assigned to my devices and done a test and it says that it is using ipv6. However on the internet connection type I still don't have an IP address populated which is very weird. I am starting to think it is there but not visually showing me in the app for some reason.