Something isn't adding up here. I've tried so many combinations and I wasn't able to reproduce your situation. This leads me to believe that your VPN provider is leaking your original IP address.
1. I opened
ikea.com using a clean browser (fresh portable Firefox). It took me to to the default locale selection page.
2. Using another clean browser, I opened
ikea.com using a Chinese proxy, I was redirected to
3. Using the same browser from step #2 (to ensure that any detection cookies or configurations are preserved) I went to
ikea.com using my normal connection. I was taken to the default locale selection page.
4. Again, I used another Chinese proxy and I was redirected to
5. Finally, I tried a U.S. proxy, and I was taken to the same locale selection page.
You're either falsifying or withholding some information, or your VPN provider is somehow revealing your IP.
In all cases I used the same browser language configurations you're using
My browser (Firefox) shows 2 languages: en-US and en.
Accept-Language header to
zh-CN,zh. I was still taken to the locale selection page.
It's safe to assume that IKEA website is pretty dumb and it's only using the IP address to determine the locale.