EX6120 connected without internet on all devices

Followed the instructions in the manual and via Youtube.

Setup both 2.4 and 5GHZ signals through the extender to the router via the mywifinext website. I did not use WPS.

All lights are green on the extender (except WPS as it is not being used).

Both laptops recognize both signals from the extender. My phone recognises both signals.

When I try connect my laptop (work or personal) or a mobile phone to either signal it connects to the extender but there is no internet connection. I have tried a 2nd mobile phone in the house. Same issue.

Both laptops are windows 10 and phones are modern.

Updated Netgear extender firmware. Same issue. Tried a reset and setup again. Same issue. Tried WPS setup. Same issue.

Firmware on extender - EX6120-V1.0.0.48_1.0.30

Router - Huawei HG633

Hardware version - H.1.01

Firmware – v2.00t (My understanding is that this is the latest version that is auto-updated by IPS Talk Talk in the UK)

Can't see any obivous settings requirements inside the router setup.

The Netgear box states: “Works with any WiFi Router”, which is a lie.

Wasted 97 minutes with this piece of Netgear junk. NOT a 5 minute activity as advertised.

All devices are able to connect fine with a BT extender that was 1/3 of the price…but needed more distance.

When trying to connect I tried turning off Wifi for all devices as well as unplugging the BT extender. i.e. the only active device was the router and the Netgear extender and the device I was trying to connect.

Read many forum posts of similar issues with NO solution.

How do I connect all devices on both signals AND have an internet connection that works?

Thanks!