In the meantime, you can fix the issue right away in your HetrixTools account by changing the "HTP Method" from "HEAD" to "GET" for any of your website monitors (by editing the monitor's settings): https://docs.hetrixtools.com/wp-content/uploads/2022/10/image.png
You can check if you're affected by this Cloudflare issue by checking your Location Fail Log (https://docs.hetrixtools.com/location-fail-log/) and looking for 520 HTTP errors.
Mar 18, 12:20 UTC