How can I fix my billing information?

So I got an iPhone 6s and I have tried do install Facebook, Messanger, etc. The problem is that it tries to make me put in a security code for a visa gift card that I never put on my Apple ID only on Xbox. We tried putting in $15 gift card to see if that would help but the same thing came up. I then looked around on here and I tried to change the billing to none like a lot of people said and but it still would not allow me to download things. Instead it would have me time in my password than take back to the billing info and just continue in that loop Then it said here was a problem with a previous purchase. Than I tried making a new Apple ID but it just connected it to my previous one without me telling it to and now I’m stuck on the loop again. Any ideas on what to do now?