Yes, You are absolutely right.
Disabling the HTTP to HTTPS rule in Cloudflare solves the problem.
I’ve added an additional rule to Cloudflare for url:
http://djzone.me/.well-known/acme-challenge/
to simply disable caching (as only one Cloudflare rule is applied, this one deactivates the other that redirect traffic to https)
As soon as the problem is resolved, I will remove the rule.
Thank you for the provided solutions!