Hi Rnick772,
Thanks for taking the time to touch base on the forum. It seems that Apple/iCloud email have decided to employ new filtering messages which are preventing our messages from getting through. At this stage we are not sure of any workaround as Apple gives little guidance on what is actually causing them to block our messages. Our emails to iCloud have been working for years but only recently they have changed something which presumably must be affecting many other services. Even our simple email message from our Gmail account saying "Your email details have been updated" is causing a rejection, so it doesn't appear that the email sender or content is the issue. If you could raise it with Apple, that would be helpful (the error is the same as mentioned in our previous post). I imagine that the more customers that report this, the sooner they will realise that their latest changes are causing legitimate emails to not come through.
In any case, we have updated your email address to the Gmail one you have provided and resent your details. If you have any further issues, please let us know.
Thanks.