I can't download apps on my IPhone?

So basically I've been okay with downloading apps in the past. However, I tried to buy an app this time and I typed in the credit card information however it didn't work. Usually, on the top in red it says what I did wrong but this time all it said was "Please contact us at www.apple.com/support/itunes/ww/." So of course I went to the address however I couldn't find the category that matched my problem. I had money in my credit card and everything, so t should have went through.
So eventually I didn't buy the app and found that it wasn't worth the effort. But then later I wanted to get a /free/ app but when I downloaded it it asked me for my credit card information again. I typed it in and it said the same thing in red that it did before. I don't know what to do at this point and I really want to download apps.

Google search this string:
"manage your apple ID"
Log in to the apple.com secure website, using Apple ID and Password.
You may be able to figure out the problem just by reviewing at your profile.

I was recently apple to create a new Apple ID without entering any credit card info,
then successfully use it to download free apps, which is why I suspect it could be issue within your AppleID user profile.

Try calling apple for help

You need to fix your itune…
need to give same address as your credit card…

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