I have enough space at iCloud, still iCloud backup fails

Hello salee_m,

There are multiple reasons an iCloud backup could fail. The "If a message says that your last backup couldn't be completed" section of If you can't back up to iCloud provides some suggestions that you'll want to check.

"If a message says that your last backup couldn't be completed

1. In iOS or iPadOS, go to Settings > Wi-Fi. Check that you're connected to Wi-Fi. 
2. Go to Settings > General, then tap Software Update. Download and install any available updates for your device. 
3. Try to back up on another Wi-Fi network.
4. Check to make sure that you have enough iCloud storage for the backup."

We hope this helps.

Cheers!