Some iCloud Mail Disappearing on iPhone

Hello Mtg22,

Thanks for checking your settings.

Is the email on your iPhone being archived? Delete and recover emails in Mail on iPhone - Apple Support

"Archive instead of delete

Instead of deleting emails, you can archive them in the Archive mailbox.

1. Go to Settings  > Mail, then tap Accounts.
2. Do one of the following:

• If you’re using an iCloud email account: Tap iCloud, tap iCloud again, tap iCloud Mail, then tap iCloud Mail Settings.
• If you’re using another email account: Tap your email provider, then tap your email account.

1. Tap Advanced, then change the destination mailbox for discarded emails to the Archive mailbox.

• When this option is turned on, to delete an email instead of archiving it, touch and hold , then tap Trash Message."

If it is not being archived only on your iPhone, and since they are still on your other devices, please contact Apple Support to investigate this with you.

Because if you deleted it, it would also delete from iCloud, then your other devices.

Contact Apple Support

Thanks.

Hello Mtg22,

Thanks for using the Apple Support Communities!

Could you please confirm if iCloud is your email provider? If so, do you currently have any rules applied that may be filtering out this message?

You can check those in here: Set up rules to filter email in Mail on iCloud.com

Checking this can help narrow down what may be happening.

Cheers!

Greetings Mtg22,

Thanks, but at this point you’ll need to contact Apple Support. They’ll have tools needed to investigate this issue further with you: Get Support

All the best.