iCloud mail since 14.4.2 upgrade
Since the iOS 14.4.2 upgrade iCloud email is not working
iPhone 12 Pro Max, iOS 14
Question marked as
Make sure that you turned on Mail in Settings on your iPhone, iPad, or iPod touch. Tap Settings > [your name] > iCloudand turn on Mail. Make sure that new data is pushed to your device automatically. In iOS 14 or later, tap Settings > Mail > Accounts > Fetch New Data, then turn on Push.
support.apple.com › en-in
If iCloud Mail isn't working - Apple Support