Change iCloud Backup from new version of iOS to older version
I have iPhone 5s with iOS 11.1. Few weeks ago had to change back my iOS version from a new version because my iPhone did not work well with the new one.
Since then I can not backup to iCloud. When I try it says:
The last backup could not be completed because it was iCloud backed up by a newer version of iOS.
How can I change iCloud to get my older version back?
Go to Settings → your Apple ID → iCloud → Manage Storage → Backup and delete the existing backup. Choose to delete and disable backups. Once the backup is removed, try to back up again from scratch.