How to restore tv app that got deleted by accident?

Hello,

Restore a built-in app that you removed

1. On your iOS device, go to the App Store.
2. Search for the app. Make sure that you use the exact name of the app. Find the correct name of built-in apps.
3. Tap to restore the app.
4. Wait for the app to restore, then open it from your Home screen.

If you have an Apple Watch, restoring an app to your iPhone also restores that app to your Apple Watch.

From:

Remove built-in Apple apps from the Home screen on your iOS 10 device or Apple Watch - Apple Support

When I search for the built in app for Mail it's there, but I can't install it. There is no "cloud" symbol for the Mail app. It just says "open". Which works (opens my mail accounts), but I want the accidentally deleted app restored to the phone home screen. iPhone 7 plus.