Hi @Gareth_85
I believe NOW customers have variable success with the NOW Hub 2 Router with third party wifi extenders.
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I am guessing you have split the 2.4ghz & 5ghz Network on the Hub Router and did a full reset on the Netgear wifi extender (maybe using the 2.4 ghz Network band off the NOW Hub Router).
I am lucky in my setup i don't need to introduce any wifi booster or upgrade to a wifi mesh system and seem to have OK coverage in my home environment.