Verification required to download apps-- but I no longer have the information required

Hello,

So I'm not exactly sure how this happened-- I believe it was when I synced my iphone with a friends so I could have music before going on a three month trip--

But I cannot download new apps.

While attempting to download a new app:

After I enter my Apple ID password, I get a "verification required" window and it takes me to a page that asks me to insert my credit card information. Only problem with this is that I have no idea what credit card information it is talking about. Says there is a visa hooked up to my account, but I've only ever had a debit master card. It could be from way back when I needed my fathers card to even have an Apple ID.... But that card is long gone by now, and I no longer have access to the security code like this "verification required" page is requesting.

Any advice on how to bypass this? Or change my billing information so that I can access downloading apps again?

Thanks so much