When any changes are made to a domain (CNAME, TXT records, name servers), it will take some time before that change is reflected across the internet. The change has to travel between root servers, web servers, and name servers, located across the world. This is known as ‘propagation’, and in some cases, it can take up to 48 hours for your website content to appear at your custom domain. Using a tool such as What's my DNS can help you follow the change you made as it propagates across servers worldwide. Check out how the change to my DNS settings propagate across the web in the GIF below.