I can't find my country code am in Rwanda

Check here: Availability of two-factor authentication for Apple ID - Apple Support

Rwanda is not on the list, but perhaps you can use 2-step verification: Two-step verification for Apple ID - Apple Support

Don't know why but Rwanda doesn't seem like an existing country to apple...

So you get stuck with that red badge on your settings icon, suggesting to use two-factor authentification which you can't...

****..