Not enough iCloud storage to back up

What it means — Apple

What to do — Apple

1. 1 Open the Settings app, then tap your name.
2. 2 Tap iCloud. At the top, you can check how much iCloud storage you've used.
3. 3 Tap Storage or Manage Account Storage.
4. 4 Tap Backups, then tap the device you're using. Next Backup Size should show you the size of the next backup. It might take a few minutes for your device to calculate Next Backup Size.
5. 5 Delete information that you don't need to reduce the size of your backup
6. 6 Upgrade your iCloud+ plan to get more space

Read the full article for pictures and model-specific details: If you can't back up to iCloud ↗