I delete Gaming Port Kit and want to redownload it again, than it happened.

I've installed the GPTK before, but it pops up with some problems so I want to reinstall it again. So I deleted home brew and redownload all the materials I needed. But when it comes to install the game-porting-toolkit formula, I can't download it, did anyone have the same problem with me?

jimmy@Jimmymbp14 ~ % brew -v install apple/apple/game-porting-toolkit
Error: Formulae found in multiple taps:
       * apple/apple/game-porting-toolkit-compiler
       * gcenx/apple/game-porting-toolkit-compiler

Please use the fully-qualified name (e.g. apple/apple/game-porting-toolkit-compiler) to refer to a specific formula.
jimmy@Jimmymbp14 ~ %