My iPhone inbox has disappeared.

Hi Bob Nellson,

Thank you for participating in the Apple Support Communities. We understand you're missing your inbox in the Mail app. You may consider restarting your iPhone to refresh iOS and the Mail app. If you've already done that, we recommend making sure you have the latest version of iOS. Here's how to update if needed: Update your iPhone or iPad - Apple Support. If that doesn't help, you can try deleting and re-adding the mail account to see if the issue persists.

"Remove your email account and set it up again

1. On your computer, sign in to your email provider’s website. Make sure that all of your email is there or make sure that your email is saved somewhere other than your device.
2. On your device, go to Settings > Mail, then tap Accounts.
3. Tap the email account that you want to remove.
4. Tap Delete Account.
5. Add your account again."

The steps above are from this article: If you can't receive email on your iPhone, iPad, or iPod touch - Apple Support.

You may also consider deleting the Mail app and reinstalling it from the App Store. Here are the steps if needed: Delete apps on your iPhone, iPad, and iPod touch - Apple Support.

We hope this helps.

Take care.