Im trying to backup my iPhone but it won’t let me it’s saying I’m to low on storage but it’s because I have over 500 MB’s of storage used on messages. How do I get rid of the messages? Or completely delete everything from my cloud? What happened is I was on iOS 11.4.1 beta then I moved back to iOS 11.3.1 for the jailbreak. So now the messages are still in the cloud for some reason.