verification required for billing address?

after removing a debit card from my billing information, i cannot download,update, or purchase anything from the app store or itunes store without a message coming up that verification is required, to “sign in to view my billing information”. when i do this, i have the billing information as none, and all the address and phone number information is correct. but for some reason i still can’t download or update anything? how do i fix this so i can purchase new apps/music and update my apps?