Unable to connect smart switches to hub 5 . Hub 3 used to work fine

[Roopal]

I have been struggling to connect my wifi sonoff switches T1 to my new virgin media hub 5 . The router is rejecting the connection. They were all working fine with hub 3.

I have already tried separating 2.4G , disable 5G when connecting. Also turned off chanel optimisation.

When called virgin media , I have been provided with a pod. Which has not made any difference .

Can anyone please help? 
Is there any port blocking with hub5? Or Strict firewall?

[Adduxi]

The Hub 5 comes with wifi 6, ax protocol.  Try setting the wifo to the legacy setting as below;

Access your Hub by navigating to 192.168.0.1
Login with the default login info (on base of Hub) unless you've already updated it.
Go to Advanced Settings > Wireless > Wireless signal
In the Wireless frequency 2.4GHz select Wireless mode > 802.11b/g/n/ax mixed
Select Apply changes

[legacy1]

Use hub in modem mode get your own router with 1Gb ports