Do I have to have a valid credit card number to download free books/apps bc I am unable to download anything at all now that my card is past it's limit

Ever since I reached the limit on my credit card I have been unable to download free apps or books. I cannot even download my new updates for my apps. Anything that requires me to put in my password is then cut off afterward with a sign saying my billing info needs to be confirmed, at which point I am taken to my billing info page and told that basically, my card is denied. It shouldn't matter if all I want to download are free items, right? I'm pretty sure I was able to download free items before I ever put in my credit card number in the first place and to not even be able to download my new updates? What should I do?