I also set up cloudflared (https://community.home-assistant.io/t/new-add-on-cloudflared) with an own domain in parallel, works well (multiple tutorials on the internet, most with freenom, but as long as you find where you can change the name servers with your hoster, it is the same), so I might move to that und just have duckdns as a backup/alternative then. The last week has been way too much lack of reliability.