Critical DNS issue

My router is not able to resolve numerous common internet domain names, including nytimes.com and washintonpost.com. I have restarted it 5 times. I am not able to reach an agent through 800-XFINITY because the AI gatekeeper thinks my router is currently in the process of restarting, and asks me to call back when it is finished. I am unable to do any work and will need to sign up for a different provider Monday if I can't get this issue resolved.