How to allow my DDNS link in Cloudflare WAF rule?

Hi, I set DDNS in my modem that need to add WAF rule to block my site for my geoip country except my IP behind DDNS, so how i can add allow rule my DDNS link in WAF?

Welcome to the Cloudflare Community!

Sadly no way I know of that you could use DDNS for that, would be expensive for Cloudflare to resolve it every time on every block/match. You could create your own automation (or find an existing) that either updates the rule filter directly or updates an IP List that the rule uses. GeoIP Country rules in general though are not what I would recommend - GeoIP Databases are not nearly 100% accurate. Usually crafting firewall rules to challenge based on other suspicious traffic factors like http/1.1 or such go further in terms of securing things, and not just being security by obscurity.