Hi there,
I’m trying to redirect the traffic from a subdomain to my netlify app using a CNAME DNS record but I keep getting a Not Found error of the form:
Not Found - Request ID: 01GJZWQ1YWN8D73ZYY162YBA2B
The problem details are as below:
marvelous-dusk-4a92fe.netlify.app
docs.microbooks.io
Looking forward to hearing from you.
Edward
Hi @ekmungai
Welcome to the community! 
I checked the deploy log for your site and can see that it was successful. I can use the permalink for that deploy to get to the page as well as go directly to the Netlify subdomain (https://marvelous-dusk-4a92fe.netlify.app)
However, I can’t resolve the page by the custom domain name. When I look at the domain settings for the domain, I see this messsage: " There’s a Netlify DNS zone for this domain, but no DNS records associated with it. Please contact support for setting up DNS records."
I then checked the DNS Zone for the site and some of the automatically-generated DNS entries appear to be missing. The first thing to try in this case is to remove the custom domain and add it back again. This will force the system to recreate the missing records.
However, deleting the custom domain will also remove any custom DNS records you may have added to the Zone manually. It looks like you may have a few. You should make a record of those entries before you remove the domain name (which removes the zone) because they will need to be recreated when you add the custom domain back.
I hope this helps! Please let us know how it goes.