how to download purchased movies without updating billing info

What actually happens when you try to redownload something ?

If you have a credit card on your account then it has to be valid and accepted by the iTunes validation. If it's not then try logging into your account on your device/computer (not when trying to download something) and see if you get the 'none' option so that you can remove the card and then try redownloading them.

If it's a different problem that you are having ... ?