This question already has an answer here:
Where can I determine what apps make the incredible size of backup?
As you can see there is almost 30GB free space, but I cannot perform a backup because there is not enough space on iCloud. Why?
Using iOS 11, iPhone 6S Plus 128GB
Under Manage Storage > Backup there is following screen:
My question is different to the marked one as duplicated, because:
- I have 50GB storage on iCloud including 30 gb free space
- using iOS 11
- my problem IS NOT about why backup still have 5GB, but why there is no space, even when backup is 20gb (what is rather impossible).