instgram apiについて

ruby言語で開発していて質問なのですが
このリクエストでエラーがでるのですが誰かこういうリクエストしたほうがいいよと分かる人がいましたら回答お願いします。
https://api.instagram.com/v1/users/search.json?access_token=himitsu&q=instagram

#使っているgemです
https://github.com/facebookarchive/instagram-ruby-gem

error内容

Instagram::BadRequest at /user_search
GET https://api.instagram.com/v1/users/search.json?access_token=himitsu&q=instagram: 400: This request requires scope=public_content, but this access token is not authorized with this scope. The user must re-authorize your application with scope=public_content to be granted this permissions.

#使っているcodeです

require "sinatra"
require "instagram"

enable :sessions

CALLBACK_URL = "http://localhost:4567/oauth/callback"

Instagram.configure do |config|
  config.client_id = ""
  config.client_secret = ""
  # For secured endpoints only
  #config.client_ips = '<Comma separated list of IPs>'
end

get "/" do
  '<a href="/oauth/connect">Connect with Instagram</a>'
end

get "/oauth/connect" do
  redirect Instagram.authorize_url(:redirect_uri => CALLBACK_URL)
end

get "/oauth/callback" do
  response = Instagram.get_access_token(params[:code], :redirect_uri => CALLBACK_URL)
  session[:access_token] = response.access_token

  redirect "/nav"
end

get "/nav" do
  html =
  """
    <h1>Ruby Instagram Gem Sample Application</h1>
    <ol>
      <li><a href='/user_recent_media'>User Recent Media</a> Calls user_recent_media - Get a list of a user's most recent media</li>
      <li><a href='/user_media_feed'>User Media Feed</a> Calls user_media_feed - Get the currently authenticated user's media feed uses pagination</li>
      <li><a href='/location_recent_media'>Location Recent Media</a> Calls location_recent_media - Get a list of recent media at a given location, in this case, the Instagram office</li>
      <li><a href='/media_search'>Media Search</a> Calls media_search - Get a list of media close to a given latitude and longitude</li>
      <li><a href='/media_popular'>Popular Media</a> Calls media_popular - Get a list of the overall most popular media items</li>
      <li><a href='/user_search'>User Search</a> Calls user_search - Search for users on instagram, by name or username</li>
      <li><a href='/location_search'>Location Search</a> Calls location_search - Search for a location by lat/lng</li>
      <li><a href='/location_search_4square'>Location Search - 4Square</a> Calls location_search - Search for a location by Fousquare ID (v2)</li>
      <li><a href='/tags'>Tags</a>Search for tags, view tag info and get media by tag</li>
      <li><a href='/limits'>View Rate Limit and Remaining API calls</a>View remaining and ratelimit info.</li>
    </ol>
  """
  html
end

get "/user_recent_media" do
  client = Instagram.client(:access_token => session[:access_token])
  user = client.user
  html = "<h1>#{user.username}'s recent media</h1>"
  for media_item in client.user_recent_media
    html << "<div style='float:left;'><img src='#{media_item.images.thumbnail.url}'><br/> <a href='/media_like/#{media_item.id}'>Like</a>  <a href='/media_unlike/#{media_item.id}'>Un-Like</a>  <br/>LikesCount=#{media_item.likes[:count]}</div>"
  end
  html
end

get '/media_like/:id' do
  client = Instagram.client(:access_token => session[:acces_token])
  client.like_media("#{params[:id]}")
  redirect "/user_recent_media"
end

get '/media_unlike/:id' do
  client = Instagram.client(:access_token => session[:access_token])
  client.unlike_media("#{params[:id]}")
  redirect "/user_recent_media"
end
get '/sample' do
  p 'iosdfjsdjfsfkjfjsd'
  puts session[:access_token]
  p 'iosdfjsdjfsfkjfjsd'
  insta = Instagram.client(:access_token => session[:access_token])
  tags = insta.tag_search('cat')
  medias = []
  5.times do |i|
    medias.concat(insta.tag_recent_media(tags[i].name, { count: 30 }))
  end
  html = ''
  for media in medias
    html << "<img src='#{media.images.low_resolution.url}' style='width: 300px;'>"
  end
  html
end
get "/user_media_feed" do
  client = Instagram.client(:access_token => session[:acces_token])
  user = client.user
  html = "<h1>#{user.username}'s media feed</h1>"

  page_1 = client.user_media_feed(777)
  page_2_max_id = page_1.pagination.next_max_id
  page_2 = client.user_recent_media(777, :max_id => page_2_max_id ) unless page_2_max_id.nil?
  html << "<h2>Page 1</h2><br/>"
  for media_item in page_1
    html << "<img src='#{media_item.images.thumbnail.url}'>"
  end
  html << "<h2>Page 2</h2><br/>"
  for media_item in page_2
    html << "<img src='#{media_item.images.thumbnail.url}'>"
  end
  html
end

get "/location_recent_media" do
  client = Instagram.client(:access_token => session[:access_token])
  html = "<h1>Media from the Instagram Office</h1>"
  for media_item in client.location_recent_media(514276)
    html << "<img src='#{media_item.images.thumbnail.url}'>"
  end
  html
end

get "/media_search" do
  client = Instagram.client(:access_token => session[:acces_token])
  html = "<h1>Get a list of media close to a given latitude and longitude</h1>"
  for media_item in client.media_search("37.7808851","-122.3948632")
    html << "<img src='#{media_item.images.thumbnail.url}'>"
  end
  html
end

get "/media_popular" do
  client = Instagram.client(:access_token => session[:access_token])
  html = "<h1>Get a list of the overall most popular media items</h1>"
  for media_item in client.media_popular
    html << "<img src='#{media_item.images.thumbnail.url}'>"
  end
  html
end

get "/user_search" do
  client = Instagram.client(:access_token => session[:access_token])
  html = "<h1>Search for users on instagram, by name or usernames</h1>"
  for user in client.user_search("instagram")
    html << "<li> <img src='#{user.profile_picture}'> #{user.username} #{user.full_name}</li>"
  end
  html
end

get "/location_search" do
  client = Instagram.client(:access_token => session[:access_token])
  html = "<h1>Search for a location by lat/lng with a radius of 5000m</h1>"
  for location in client.location_search("48.858844","2.294351","5000")
    html << "<li> #{location.name} <a href='https://www.google.com/maps/preview/@#{location.latitude},#{location.longitude},19z'>Map</a></li>"
  end
  html
end

get "/location_search_4square" do
  client = Instagram.client(:access_token => session[:access_token])
  html = "<h1>Search for a location by Fousquare ID (v2)</h1>"
  for location in client.location_search("3fd66200f964a520c5f11ee3")
    html << "<li> #{location.name} <a href='https://www.google.com/maps/preview/@#{location.latitude},#{location.longitude},19z'>Map</a></li>"
  end
  html
end

get "/tags" do
  client = Instagram.client(:access_token => session[:access_token])
  html = "<h1>Search for tags, get tag info and get media by tag</h1>"
  tags = client.tag_search('cat')
  html << "<h2>Tag Name = #{tags[0].name}. Media Count =  #{tags[0].media_count}. </h2><br/><br/>"
  for media_item in client.tag_recent_media(tags[0].name)
    html << "<img src='#{media_item.images.thumbnail.url}'>"
  end
  html
end

get "/limits" do
  client = Instagram.client(:access_token => session[:access_token])
  html = "<h1/>View API Rate Limit and calls remaining</h1>"
  response = client.utils_raw_response
  html << "Rate Limit = #{response.headers[:x_ratelimit_limit]}.  <br/>Calls Remaining = #{response.headers[:x_ratelimit_remaining]}"

  html
end