Ruby error: cannot load such file -- rest-client

I am using Ruby on Rails 4. I am trying to ``` require 'rest-client' ``` in my controller so that I can parse the login information I am getting from a form and send it to an API. I can verify that the gem is installed and is also in my Gemfile on the application root. However, it is still throwing the "cannot load such file -- rest-client " when I try to require the file in my controller. I have googled the error and most of the answers I saw were either the gem wasn't installed, wasn't in the Gemfile, or a combination of both those. Neither is the situation here. Is my controller unable to access the rest-client gem for some reason? I have to use rest-client because it is required in the API. This is the line I used to install the gem: ``` gem install rest-client ``` This is the homepage of the gem: https://github.com/archiloque/rest-client Which just redirects you to https://github.com/rest-client/rest-client I should also note that it works fine when I wasn't using the code in a Rails project but just running the commands in the Terminal.