iCloud storage accuracy issues on my all Apple devices

I have an iPhone, iPad and Mac Air. I have 3.9GB backup on iPhone, 8.9GB backup on iPad and I just got the MacAir have no backup on iCloud for it yet. With my wife’s iPhone, I have total of 16.8 for family. However, all devices are now showing I have 334GB being used. Yet, on all devices, when I look at iCloud storage on the device, there are no iCloud files that show up with hardly any storage. Help!

[Re-Titled by Moderator]

Original Title: iCloud storage accuracy issues