Unable to login to Apple ID, says the Apple ID is "not active".

My daughter created an apple ID on apple website using her gmail email address. When she tried to sign in to her new iphone using her ID, she is getting a message that the ID is not active. She tried to reset the password and got the same message that ID is not active. When she tried to create a new apple ID with same email address again, it says that ID is already taken and not available.

So the apple ID is not active and not available. How can she get her ID back?

[Re-Titled by Moderator]