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For a few weeks the wifi on my TV kept dropping out and needing reconnected, it now won't connect at all, it is connecting to the network but not the internet. I have reset router, TV, wifi, forgot & reconnected the wifi, manually set DNS on router and TV, (which after a lengthy webchat with Vodafone was assured would definitely work) and nothing is making any difference. Phone and tablet are connecting fine.
More and more these kinds of issues look as though they are associated with Vodafone's "content filtering", which still seems to kick in even if you've turned it off in your account settings (not a router setting).
If you've not already done so it's probably best to manually set your DNS servers to some combination of those from Cloudflare 22.214.171.124 & 126.96.36.199 and Google DND 188.8.131.52 & 184.108.40.206
Personally, if I were using these I'd use one from each!
*You can normally set these on the router or in some cases you could set them directly on the TV.