Q: Everytime I tried to download a free app it says that I need to put in my billing information as if it cost. How do I fix it?

a few days ago I accendently deleted snapchat and I went back to tried to download it at the Apple Store and it says I need to put in my billing information. I'm kind of confused because snapchat is free as most know. I tried another app to see if it would work and it didn't. I also thought that maybe logging out of my iCloud account would work or maybe turning my phone off and it still remained the same . Idk of resetting my phone would help but I forgot my restrictions password. I need help!!