Cannot auto format go (golang) code in vim

I was having a problem with the following command:

autocmd FileType go autocmd BufWritePre <buffer> Fmt

its suppose to format my code code automatically by putting it at the end of my .vimrc file.

This is how my .vimrc file lookgs like:

set nocompatible              " be iMproved, required
filetype off                  " required

" set the runtime path to include Vundle and initialize
set rtp+=~/.vim/bundle/Vundle.vim
call vundle#begin()
" alternatively, pass a path where Vundle should install plugins
"call vundle#begin('~/some/path/here')

" let Vundle manage Vundle, required
Plugin 'gmarik/Vundle.vim'

" Keep Plugin commands between vundle#begin/end.
" plugin on GitHub repo
Plugin 'tpope/vim-fugitive'
" plugin from http://vim-scripts.org/vim/scripts.html
Plugin 'L9'
" Git plugin not hosted on GitHub
Plugin 'git://git.wincent.com/command-t.git'
" git repos on your local machine (i.e. when working on your own plugin)
Plugin 'file:///home/gmarik/path/to/plugin'
" The sparkup vim script is in a subdirectory of this repo called vim.
" Pass the path to set the runtimepath properly.
Plugin 'rstacruz/sparkup', {'rtp': 'vim/'}
" Avoid a name conflict with L9
Plugin 'user/L9', {'name': 'newL9'}
Plugin 'commentary.vim'
Plugin 'go.vim'

" All of your Plugins must be added before the following line
call vundle#end()            " required
filetype plugin indent on    " required

syntax on
filetype plugin on

filetype indent on

"autocmd FileType go compiler go
autocmd FileType go autocmd BufWritePre <buffer> Fmt

However, vim does throw me an error saying:

Error Detected while processing BufWrite Auto commands for "<buffer=1>"

E492: Not an editor command: Fmt

I have no idea whats wrong, specially because it was working earlier.

You're probably referring to the :Fmt command defined by this.

It looks like that filetype plugin isn't sourced. You can check with the :scriptnames command; it needs to contain ftplugin/go/fmt.vim. If it isn't, something's wrong with your 'runtimepath' option.

Alternatively, you could use fatih/vim-go; it apparently has a configuration that automatically formats the Go source code, so you don't need to define that :autocmd on your own.