BT Smart Hub 2 Wi-fi problem

[j2020]

The Wi-fi on the BT Smart Hub 2 has suddenly stopped working.
Broadband and Digital Voice are working.

I have tried switching the hub off for a while, resetting/changing the Wi-fi password, doing a factory reset.
The 2.4GHz Wi-fi no longer displays a Smart channel number even after rescanning several times. Manually setting a channel does not resolve the problem.
The 5GHz Wi-fi shows a Smart channel number and sometimes a different one after rescanning.
Switching the 5GHz Wi-fi off does not resolve the problem, devices are still unable to connect to the 2.4GHz.
Switching the 2.4GHz off, devices that can use 5GHz do not see anything.

The Smart hub is clearly faulty.
Contacting BT using the online chat did not achieve anything.
They refuse to send a replacement hub and a return label for the faulty one.
They want to send an "engineer" at a possible cost of £85 and they say the "engineer" will not bring a replacement Smart hub.

[licquorice · Accepted solution]

Call customer services on 0800 800150 and be insistent the hub is faulty and you need a replacement.

[j2020]

Thank you for your suggestion. Speaking to someone on the telephone resulted in a replacement hub being sent which cured the problem. The next bill had a £9.99 charge on it for sending the hub which I complained about and it has now been credited for the next bill.