I am currently trying to set up Unity payment and it is automatically checking off withholding?

I am currently trying to set up a Unity payment profile and it is automatically checking off backholding on the W-9 thing? It says I am not subject to it on the actual document, but on the last step, it forces me to say I am. What is going on? I am over 14 but under 18, should I use my parents name instead? Help me! Here is an Imgur link that contains some screenshots: Imgur: The magic of the Internet

Please help me!