diff --git a/app/controllers/installations_controller.rb b/app/controllers/installations_controller.rb
index 66baf1050..f7bf4f0d6 100644
--- a/app/controllers/installations_controller.rb
+++ b/app/controllers/installations_controller.rb
@@ -94,7 +94,7 @@ class InstallationsController < ApplicationController
     @access_token = Doorkeeper::AccessToken.create!({ :application_id => @application.id,
                                                       :resource_owner_id => @bot.uid,
                                                       :scopes => "public write",
-                                                      :expires_in => "604800",
+                                                      :expires_in => "2592000",
                                                       :use_refresh_token => true
                                                     })
     @install_bot.update_attributes!(state: 1)