BBC are good at not playing when you have a UK VPN (or rather are good at blocking VPNs). I get failures when I use a UK VPN from within the UK.
In my case i'm connecting from outside UK, hence the VPN. Strange thing is I also have a TV which has a amazon fire tv stick with vpn app and kodi through which iPlayer works fine.
I installed the ITV addon which requires UK IP, so that at least shows that my VPN is working.