DNS and ip


I have a vpn (openvpn with openwrt firmware) and I decided to try the dns and cause of that, when I’m connected to France server, my IP geolocation is in france but the dns always appears in germany. So when I try to watch netflix with French libraries, I have the German language content. Also, since I use that dns, on my cell phone, when I’m outside of my wifi network, when I use my ISP internet service, my real ip has changed now…
Do you have an idea?