iPhone Pro Max tells me I don’t have more storage

Here’s article explaining storage and iCloud. It explains the things to check for and why you’re seeing this alert.

https://support.apple.com/en-us/HT203516

Get help backing up your device with iCloud Backup

Learn what to do based on the issue that you experience or the message that you see.

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

A message appears when you need more iCloud storage to back up (the available space on your iOS or iPadOS device is different than your available space in iCloud).

Here's how to find your Next Backup Size:

• On iOS 11 or later and iPadOS: Go to Settings > [your name] > iCloud > Manage Storage > Backups. Tap the device you're using.
• On iOS 10.3: Go to Settings > [your name] > iCloud > iCloud Storage > Manage Storage. Tap the device you're using.

After you check to see how much iCloud Storage you have, try these steps to complete your backup:

1. Upgrade your iCloud storage plan.
2. Reduce the size of your backup.
3. Delete any data that you don't need.
4. If you still need help, contact Apple Support.

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

1. Check that you're connected to Wi-Fi.
2. Ensure your device is up to date.
3. Try to back up on another Wi-Fi network.
4. If you still need help, contact Apple Support.

What is iCloud Drive?

With iCloud Drive, you can securely store your files in iCloud and access them on iCloud.com and your iPhone, iPad, iPod touch, Mac, and Windows computer. You can also have all the files in the Desktop and Documents folders on your Mac stored automatically in iCloud Drive. That way, you can save files right where you usually keep them on your Mac, and they become available on iCloud.com and all your devices.

On iCloud.com, you can use iCloud Drive to upload and download files, share files, delete files, organize files in folders, rename files, and recover recently deleted files. You can also share folders of files with other iCloud users. If you have Pages, Numbers, or Keynote files stored in iCloud Drive, you can open them in Pages, Numbers, or Keynote on iCloud.com.

To use iCloud Drive on iCloud.com, go to icloud.com/iclouddrive and sign in using your Apple ID. Make sure to use a web browser recommended in the Apple Support article System requirements for iCloud.

For more information about iCloud storage and family storage plans, see Upgrade or downgrade your iCloud storage.