CNAME not correctly loading page

Hey all, I'm trying to create a file host with a custom subdomain system. It's a bun reverse proxy that takes in the subdomain, fetches new content based on that subdoamin, then returns it. Going directly to the url https://govb12ewwx1q.s.myfileho.st/ displays the contents of the page. So, I created a CNAME portfolio govb12ewwx1q.s.myfileho.st yet it gives a ERR_QUIC_PROTOCOL_ERROR after multiple minutes of waiting. Anyone know what the issue could be?