iCloud Email Alias can only Send, Received Messages Bounce Back to Sender
I created an email alias in iCloud mail (webmail) and can successfully send messages from it within iCloud mail. However, all replies sent to it are returned to the sender as undeliverable. Everything I've read here indicates they should be able to send and receive, why is it that this one cannot get messages? Is there a setting I'm unaware of that I need to check so that the alias is not limited to send only?
Windows, Windows 6