Are you travelling? Because my domain blog.bjrn.se is simply a CNAME to blogspot. They have some weird redirection thing going on so if I visit their website I will get redirected to the local version, which always confuses me (as I often travel).
Yes, I was travelling, so I was coming in on a Norwegian IP address. The cookie message was in Norwegian, which I don't speak, and covered most of the screen. That was on my phone.
Now I'm on my laptop. There's no banner, so I don't know if it would switch language.
Hope that helps.