:HashWithIndifferentAccess error in rails

[jakx12]

Hey ok so im getting this error. no idea why, could you guys help?

Controller action -

def confirm
    @title = "Confirm"
    if request.post?
      confirmation = params[:confirmation]
      account = Account.find_by_username_and_confirmation_code(params[:confirmation].username, params[:confirmation].code)
      if !account.nil?
        account = Account.update_attribute("confirmation_code", "")
        if account.save
          flash[:success] = "Congratulations you have now confirmed your email!"
          redirect_to :action => "index"
        end
      else
        flash[:error] = "Incorrect confirmation code or username."
      end
    end
  end

view -

<% form_for :confirmation do |form| %>

<label for="username">Username:</label>
<%= form.text_field h(:username), :size => 20 %>
<label for="code">Confirmation Code:</label>
<%= form.text_field h(:code), :size => 30 %>

<%= submit_tag "Confirm", :class =>'submit' %>
<% end %>

heres the full error:

NoMethodError in AccountController#confirm

undefined method `username' for {"code"=>"", "username"=>""}:HashWithIndifferentAccess
RAILS_ROOT: /Users/Zack/Desktop/General/Rails/verges

Application Trace | Framework Trace | Full Trace
/Users/Zack/Desktop/General/Rails/verges/app/controllers/account_controller.rb:82:in `confirm'
Request

Parameters:

{"confirmation"=>{"code"=>"",
 "username"=>""},
 "commit"=>"Confirm",
 "authenticity_token"=>"L9+134xxYjYu0qc198BGRQnZ3wBXV2Ktg74pVSotWtk="}
Show session dump

Response

Headers:

{"Content-Type"=>"",
 "Cache-Control"=>"no-cache"}

Many thanks,

jakx12