I upgraded my 5GB iCloud storage to 50GB storage and its not showing
The easy way to make sure Apple has provisioned your storage is to sign in to iCloud on a computer with a somewhat modern browser:

https://www.icloud.com/#settings

If the cloud doesn't see your storage, you have a billing and/or support question.


https://support.apple.com/itunes


If the cloud does show your storage, you can get free support using the paid storage as an exception from AppleCare at:


https://support.apple.com/ - choose your device that's not able to get the paid storage.