iMessage broken
My imessage on both my computer and phone will not allow me to log in. Every time I log in on my computer it says 'an error has occurred during authentication' and when I try to log in to my phone it freezes. This problem also happens with my facetime. I have created three different accounts and they all do the same. I have checked for correct date&time, internet, turned imessage and facetime off and on and tried restarting my phone and computer. They are also both up to date with the latest IOS update. How do I fix this problem? Is it to do with my icloud?
iPhone 6s, iOS 11.1, Macbook Air