So UPnp and port forwarding will keep you in NAT 2 but its way safer than NAT1 or the DMZ.
Exactly how you do that depends on what router you have although the process is pretty much the same. You'll need a static IP for the PS4 and then forward these ports.
TCP: 80, 443, 1935, 3478-3480
I don't use TT routers so I don't know what part of the interface you need on your specific router to do this but basically you need to forward the TCP & UDP ports to the PS4 IP address.
Possibly @KeithFrench can help with this as he has a very good knowledge of TT firmware and UI not to mention networking in general.
Is your internet connection ok other than for gaming on the PS4?
Never use UPnP it is very insecure, always use port forwarding instead.
Before I can help with the port forwarding I need to know the make/model of TalkTalk router that you have.
I am not employed by TalkTalk, I'm just a customer. If my post has fixed the issue, please mark it as the Best Answer.
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