CNAME from aws route53 to CF hosted server

I am trying to route an external; sub-domain to Cloudflare hosted domain transparently. aliast to

I added the above CNAME record in route 53. This gives an error in Cloudflare as below. please help and best way to approach this. I do have an IP address for the server but rather want to redirect via the CNAME approach.

Error 1001 Ray ID: 38e419a2e3a42e51 • 2017-08-14 13:00:58 UTC
DNS resolution error
What happened?
Most likely: if the owner just signed up for Cloudflare it can take a few minutes for the website’s information to be distributed to our global network.
Less likely: something is wrong with this site’s configuration. Usually this happens when accounts have been signed up with a partner organization (e.g., a hosting provider) and the provider’s DNS fails.

Based on your description above I don’t believe you’re passing the host header of the domain hosted on Cloudflare in the request. So when the request comes in for Cloudflare doesn’t understand who/what the traffic is for and can’t then route it to a destination.