DNS error assist pops up when browsing

​Hello,​

​When I’m using the Wi-Fi on my phone and I go to search something on safari or even google app it keeps redirecting me to a DNS error assist URL and I’ve read others having this issue a couple years ago and I tried the links to turn this off on AT&T but 1. The links don’t work and 2. If I try to search the help pages on AT&T nothing comes up. If someone could tell me how to turn it off I’d greatly appreciate it. ​