Hello, @naijapropertyhub,
I have just checked your provided site and the Cash On Delivery is there on the checkout page and working fine, please see this screenshot: https://postimg.cc/sBs51tQG so it must be the cache issue only at your end nothing else.
Please try to check the site on any other Computer on a fresh new browser, I am sure you will not find this issue anymore.
Regards 8Themes Team.