Issue with Using Fastly CDN with Render Custom Domain

I’m trying to use Fastly as a CDN in front of my Render service and set up a custom domain, but I’m running into some issues.

I’ve set up the service on Render and added my custom domain, but I’m unable to verify the domain because I need to point it to Fastly. When I point my domain to Fastly, I get a 421 Misdirected Request error.

How can I properly verify my custom domain with Render while using Fastly? Should I temporarily point the custom domain directly to Render for verification and then switch to Fastly afterward, or is there another solution?

Any help would be appreciated!