So let me tell you i got an Iphone and i have family with my mum right now...We did the icloud for 50GB!We only used 15GB an when my mum wants to backup she cants it tells like she cant backup get more storage and we only used 15GB...But when i backup its okay!
iPhone 15, iOS 26
"Unable to back up iPhone despite available iCloud storage: So let me tell you i got an Iphone and i have family with my mum right now...We did the icloud for 50GB!We only used 15GB an when my mum wants to backup she cants it tells like she cant backup get more storage and we only used 15GB...But when i backup it's okay!"
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iCloud Upgrade Not Working 100%:
A. Confirm the Upgrade:
Go here, and confirm that the upgrade went through successfully: View or cancel app subscriptions on iPhone - Apple Support
B. New iCloud Session:
Having just performed the iCloud Storage Plan upgrade, log out of iCloud on all of your devices, and then log in, one item at a time.
C. Links on Troubleshooting iCloud Backups:
You won't be able to tell if the issue is due to your use of the beta software (iOS 26) or not, until you remove the beta using the instructions. It is expected that many things are not going to work correctly when testing the beta, which is why there is no support and you are directed to log any issues using the Feedback Assistant. As with previous beta releases, iCloud incompatibilities are common. That is also why you cannot use the iOS 26 beta backup when you restore to iOS 18, and results in complete data loss without that iOS 18 backup.
You are at the point now if you want to wait it out until the release version is available and live with any issues you encounter since there is no support, or remove the beta in an attempt to resolve the problem. That is up to you.
How to uninstall iOS or iPadOS beta software - Apple Support
Unable to back up iPhone despite available iCloud storage
