Catch-All Mail issue and problems with activating @icloud.com-Mail to configure iCloud-Mail Service

Hi,

so I've decided to switch from my self-hosted mail inbox to iCloud-Mail since everyone in my family uses Apple Products now.

I've had a few inboxes for services like Netflix which I tried to add right away but realised that you're limited to only 3 addresses per account so I've deleted the unnecessary and enabled Catch-All functionality only to quickly realise that I can not recieve emails to that inbox anymore.

Example: I've deleted netflix@example.com and enabled Catch-All instead. Now no mails can be delivered to that address and I get an error message "Remote Server returned '550 5.1.6 user no longer on system:netflix@example.com'" instead, when some random address like djgfokdfgdjfg@example.com does work.

Further more I've had difficulties to get iCloud-Mail to work on every phone in my family where I can't create the standard @icloud.com mail to get it configured and also get an error message instead.

Since Apple makes it extremly hard to get in touch with them via text I've decided to ask the community if you've had similar issues and had a quick fix for me.