Urn:ietf:params:acme:error:connection Status: 400 Timeout after connect (your server may be slow or overloaded)

curl works from my location

$ curl -Ii http://climatech.ps/.well-known/acme-challenge/somtestfile
HTTP/1.1 404 Not Found
Cache-Control: private
Content-Length: 3208
Content-Type: text/html; charset=utf-8
Server: Microsoft-IIS/10.0
X-AspNet-Version: 4.0.30319
X-Powered-By: ASP.NET
X-Powered-By-Plesk: PleskWin
Date: Sun, 26 Nov 2023 23:33:46 GMT

This never completes even after minutes!
Do you a have a Palo Alto Firewall?
This is emulating how Let's Encrypt makes the request to the server.

$ curl -Ii http://climatech.ps/.well-known/acme-challenge/somtestfile -A "Mozilla/5.0 (compatible; Let's Encrypt validation server; +https://www.letsencrypt.org)"

Please see:

and another recent thread

Ports 80 & 443 look Open from my location.

$ nmap -Pn -p80,443 climatech.ps
Starting Nmap 7.80 ( https://nmap.org ) at 2023-11-26 23:37 UTC
Nmap scan report for climatech.ps (
Host is up (0.20s latency).
rDNS record for plesk02.hadara.ps

80/tcp  open  http
443/tcp open  https

Nmap done: 1 IP address (1 host up) scanned in 1.03 seconds
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