Hello and welcome to Apple Support Communities rodoliver,
I see that you're getting an error message when trying to manage your iCloud storage. I can understand wanting to get this resolved, and I'd be happy to help.
Let's start by having you sign out of iCloud and restart both devices and then try again.
Sign out of iCloud on your iPhone, iPad, iPod touch, Apple TV, or Mac
If the issue remains, take a look at the article below that can help.
Manage your iCloud storage
If the issue remains, respond back with some more details. Are you connected the internet? Which version of software are you using on your devices? Have you been able to manage your iCloud storage from either device in the past?
Thank you for using Apple Support Communities.