After adding a CNAME record in your Domain Host it is a good idea to test if the record was created as expected.
You can use https://dnschecker.org to test the record.
Steps to Test Your CNAME record:
Go to https://dnschecker.org
Input your custom domain including subdomain. Do not include http:// or https:// (ex. www.your-site.com or courses.your-site.com)
Change from A to CNAME in the selection box
Click on Search button
If your CNAME record was created successfully, you will see the result like,
