The Federation Service encountered an error while retrieving the federation metadata

Question

ADFS server can't renew a relying party trust metadata automatically.
In logs I see:

The Federation Service encountered an error while retrieving the federation metadata document from 'https://myDomain.cloudflareaccess.com/cdn-cgi/access/saml-metadata'. The monitoring for the following trusts failed:

Claims providers:

Relying parties:
myDomain.cloudflareaccess.com

Additional Data

Exception details:
The remote name could not be resolved: 'http'

Additional details:

User Action
Make sure federation metadata URL is accessible.
Verify your proxy server setting. For more information about how to verify your proxy server setting, see the AD FS Troubleshooting Guide (http://go.microsoft.com/fwlink/?LinkId=182180).

But if I try to update the relying party trust manually via UI - it works.