WHy my backup to icloud is not working on my computer even when circle checked for this?

[iMore Question]

I bought extra icloud storage thinking that this was the reason the backup to icloud was not working on my computer when I plug in my iphone and press sync or backup.
BUT whatever I do, even check the circular box asking icloud or this computer, it will never backup to icloud. It says this phone has never been backed up to icloud. Any ideas?

 

[kch50428]

https://support.apple.com/kb/PH12520?viewlocale=en_US&locale=en_US