Thanks for all your answers! I will check some of the alternatives to duckdns.

I have a domain… but I think DynDNS is not always available for every domain or by every domain seller?

In my case, there is no IP change. However, the TTL of entries seems to be 60 seconds and when Cloudfare/Google asks for the new A record, it sometimes fails. I am getting this error message from Cloudfare when I try to solve host.sub-domain.duckdns.org

EDE: 22 (No Reachable Authority): (time limit exceeded)