I have been using Cloudflare DNS (126.96.36.199/188.8.131.52) on my router at home for a long time. However, for the past few months, I have not been able to access to w3schools.com. When I delete Cloudflare DNS on my router, I can access it. What do you think could be the problem? Another Turkish user has created a thread (W3schools.com cannot be resolved in 184.108.40.206 (but resolvable in 220.127.116.11)) about this problem. Is it a problem with Internet Service Providers or Cloudflare Data Center in Turkey?