Q: Changed iCloud ID issue

I have a problem with my iCloud account - briefly: I change my apple user ID from an old email address to my new one, however I forgot to change the iClound user ID first.

So I have a problem that my iCloud wants the password for the account of the old email address, even though my apple user ID is now a new email address. Every time I enter the the old password in icloud (for the old email address), and even when I try the new password it says its wrong.

It seems when I made the change to the new user ID, I should have changed the icloud user id first. I have no way of changing the icoud id without the password, I don't have a password because the ID has changed.???

Is there anyway of changing the icloud id to the new apple user ID on my phone???

Regards

Lee