You are likely affected by a Palo Alto Networks brand firewall. Check its Application Rules for something like "acme protocol" and ensure it is allowed.
Test requests to your domain timeout but only for requests to the acme challenge that also use a "user agent" string the same as Let's Encrypt server uses. See below for a different person who had this same problem.
Just substitute your domain name for the ones in that post and yours fails in the same way. Specifically:
curl -I -m10 air.cs.itu.edu.tr/.well-known/acme-challenge/TestForum123 -A "Mozilla/5.0 (compatible; Let's Encrypt validation server; +https://www.letsencrypt.org)"
curl: (28) Operation timed out after 10001 milliseconds with 0 bytes received
curl -I air.cs.itu.edu.tr/.well-known/acme-challenge/TestForum123
HTTP/1.1 404 Not Found
Date: Thu, 04 Aug 2022 14:16:56 GMT
Server: Apache/2.4.29 (Ubuntu)
Content-Type: text/html; charset=iso-8859-1