Error 1016 Unable to create DNS A record

Almost there!

This one typically means that the “Service” you entered into your Public Hostname is incorrect or is in fact returning a 502 response itself.

You can see the full corresponding error by checking the logs for the cloudflared process on your setup. If it contains Unable to reach the origin service then this means that the service configuration is incorrect. Which is certainly odd because those are the ones you specify in your original post. Can you check the logs and share the error lines here?