Game Controller

Hi all, I have looked far and wide for help but I think I need some more step by step help. I am trying to make a 14 button gaming controller using an Arduino Pro Micro. I have 12 of the buttons grounded together, and the other pins connected to 2-7 and A3-A0, 14 and 15. the other 2 buttons are connected to pins 8 and 14, and they are grounded to the pin next to them. I am trying to use the code included here (https://www.thingiverse.com/thing:4058270) but I get an error saying "'JOYSTICK_DEFAULT_REPORT_ID' was not declared in this scope"

I know this is a long help request, but I am lost. thanks for any help!

How is this a bootloader issue?

Why can’t we see your code?