Family Plan issues with Storage

I have I have 200GB plan which I share with family of 4. Been Like this for a few years. But always the one family member when I look them up on list it says "not used" for icloud backup. But meanwhile they are getting backup.

Now yesterday they got a message that their icloud+ storage nearing full. When I look on their phone under Settings/UserName/iCloud/ it shows 199gb of 200gb used. But meanwhile on my phone it shows 124gb of 200 Used.

I was going to just upgrade to 2tb if can't fix issue.