Completing Apple ID

Recently, every time I try to update or download certain apps, it won’t let me because “This Apple ID has not yet been used in the iTunes Store.” It’ll give me an option to review my account in which I do. It’ll have me complete my Apple ID with payment method, in which I chose none. However it’ll give me a screen that says “we’ve run into a problem. Try again later.” It’s been like this for a couple weeks now, so I tried to use a card, but I got the same results. How do I fix this?