I got a new Talktalk fibre hub in September and initially it was working well and giving a far superior WiFi coverage than the old HG533 router. After about 6 weeks, the WiFi started to drop connections to my Alexa devices, 2 android phones and iPhone. Ethernet connected devices were not affected. If the hub is left long enough, it will sometimes reconnect the WiFi, but usually I have to turn off the router, wait and then turn it back on.
Running the system stays check never shows up this intermittent fault. I have tried the online chat but that failed miserably after 50 minutes after trying to answer totally irrelevant questions and finally having the chat terminated without warning. When I said I could send a copy of the router log showing the disconnections , she wasn't interested and wanted to send a chargeable engineer to upgrade the WiFi. It just made no sense.
I have tried a factory reset which made no difference.
I see other people having similar problems are offered a replacement hub to try.
I hope that someone out there can help to resolve the issue in the same way that others with the same problems have been helped.