What should I do if my Apple ID Is not recognized in the App Store?

I just received a new MacBook Pro 13 and was trying to add new apps for my college classes. When trying to download an app for the first time I was told to review my Apple ID information because it wasn’t used in the AppStore yet. When I clicked okay, it asked for my billing information. After putting in my correct billing information it then only told me at the top to contact itunes support. I don’t understand what I am doing wrong. All of my information is correct and I have put in all of my payment information. Please help!

[Re-Titled by Moderator]