Dear Team,
Sorry that I am NEW here and not sure if this is the right place for posting my question below and appreciate if any professional & experts can advice on it.
We are hosting our DNS in Cloudflare and there are a few cases in which this DNS cannot be looked up by our 3rd party service vendor (Mailgun) and thus they are not able to send us routing email to our Web Server URL path for further processing.
Here is the reply from our 3rd party vendor for your reference and thanks all in advance.
Thank you all again.