iCloud backup attempt failed on iPhone

Few things come to mind:

• Not enough space on iCloud
• Bad/poor Wi-Fi connection
• Temporary glitch

First thing I would do would be to check if you’ve got enough iCloud storage. If that’s not the issue, try restarting your device and make sure you’ve got a strong Wi-Fi network connection.

Here’s a helpful Apple Support link: If restore from iCloud backup failed - Apple Support

andysims wrote:

Here’s a helpful Apple Support link: If restore from iCloud backup failed - Apple Support

This article doesn't seem to apply to having problems creating an iCloud backup.

Yes, has andysims suggests, check your iCloud storage.

When I click on the little arrow next to ON, I see a menu that includes "Back Up Now." What happens when you try that?