There are other services which should work for you as well. I use one which never requires a regular check in. They even ofter a command line curl or other methods to send your updated IP to it. Think Home Assistant, via a curl or if you have a router with Freshtomator or other which supports such curl, it will work as well.

freemyip.com

I’ve been using them for a few years now and never ever had an issue with uptime or otherwise. My use is just as a backup in the event my VPS goes down which hosts Pangolin (VPS).

Others such as noip.com and such do work well also.