DNS error while accessing website

Trying to access a website (https://patientgateway.massgeneralbrigham.org/) results in the following error:

This site can’t be reached

patientgateway.massgeneralbrigham.org ’s DNS address could not be found. Diagnosing the problem.
DNS_PROBE_POSSIBLE

I am using cloudflare dns (1.1.1.1) and the cloudflare vpn with Brave when I get the error, but with Safari the same website works without error (with the same dns and vpn).

I can access any other website with Brave without error (with the vpn enabled).

When I turn off the vpn I am able to access the website with Brave without error. So, it is the combination of Brave, the vpn, and the website that doesn’t work. Very bizarre.