Why do some sites e.g. BBC Sounds & National Lottery not recognise AVG VPN UK Locations as in the UK?

AVG Secure VPN
1

I am physically located in the UK and my ISP is BT. Recently when using AVG VPN UK locations with BBC Sounds I get a message “ We’re replacing BBC Sounds outside the UK and bringing you BBC.com, a seamless way to read, watch, and listen - all in one place.”. The UK National Lottery site never allows me to log in while using the VPN. “ It looks like you’re outside the UK and Isle of Man”. Why do these sites not recognise AVG VPN UK locations?

2

This is what the BBC says about VPNs