My friend, as far as I know, some of the providers are blocking this service. Speaking from my personal experience when I was visiting Russia they blocked a lot of services that used to use on a day by day basis. So, maybe, this could be your providers issue, at least your Internet providers issue, as I don't know anything about phone technologies. So, if somebody else has this kind of issue, but struggling it on their PC or laptop's you can try to change your provider as some of them are blocking. If you will be looking for the best provider in your area you can use https://usave.co.uk as it will make this much much easier. You will need to introduce your postcode and the main criteria of your Internet preferences and they will match you the best options available. So go on and try