Change Apple ID to alias@icloud.com
I am trying to change my Apple ID login email address, which has been an email address of an external email provider forever.
As I would not like to use my cumbersome primary @icloud.com address, I created a more elegant alias @icloud.com address for my primary @icloud.com address specifically for that purpose.
When I now go to the AppleID section on appleid.apple.com and try to change my AppleID to the newly created alias@icloud.com address, it only says, that I should continue on one of my devices. Apart from that, nothing happens and I also can’t find anything in my device settings to change the AppleID address.
So how can I change my AppleID address from my current email address of an external email provider to my newly create alias address from @icloud.com?
iPhone 13 Pro, iOS 17