phone won't backup with only 2.5gb used of 5gb total

Hello CrappieFisherman,

We would like to see how we can help you with your iCloud backup. This is expected behavior of the size of your backup is larger than the 2.5GB that is free on iCloud. Follow the steps in this link for more information: If you can't back up to iCloud

"If an alert says that there's not enough iCloud storage

1. In iOS or iPadOS, go to Settings > [your name].
2. Tap iCloud. At the top, you can check how much iCloud storage you've used.
3. Tap Manage Account Storage or Manage Storage.
4. Tap Backups, then tap the device you're using. Under Last Backup and Backup Size, you can check Next Backup Size. It may take a few minutes for your device to calculate Next Backup Size. 
5. If your backup needs more space than the amount you have available in iCloud, you can: 

• Delete information that you don't need to reduce the size of your backup
• Upgrade your iCloud+ plan to get more space

If you still need help, contact Apple Support."

Cheers!